Implement Slack integration for pipeline hooks

## What does this MR do?

Add pipeline events to Slack integration

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- Tests
  - [x] Added for this feature/bug

See merge request !5525

Add bulk update support for merge requests list

## What does this MR do?

Adds new feature: ability to update multiple merge requests at once from index page (same like we have for issues already)

## Are there points in the code the reviewer needs to double check?

I don't think so

## Why was this MR needed?

* consistency with issues
* save user time when you want set same label/milestone to 20 merge requests 

## Screenshots (if relevant)

![Screenshot_2016-09-08_11.48.49](/uploads/fe50b2472330e211eb8d6d6dafb15667/Screenshot_2016-09-08_11.48.49.png)![Screenshot_2016-09-08_11.48.46](/uploads/4833c3705120ec028f7a62a4e128998d/Screenshot_2016-09-08_11.48.46.png)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] ~~[Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)~~
- [x] ~~API support added~~
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/20087

See merge request !6226

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Fix margin for awards-control buttons

## What does this MR do?
Fixes margin in awards-control

## Screenshots (if relevant)
Before:
![Screen_Shot_2016-09-06_at_10.58.03_AM](/uploads/b3fcd4103669bc7ae54a22093f492391/Screen_Shot_2016-09-06_at_10.58.03_AM.png)

After:
![Screen_Shot_2016-09-06_at_10.54.54_AM](/uploads/dcd0e57a8cff82fe70990a9a8e2b1232/Screen_Shot_2016-09-06_at_10.54.54_AM.png)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
https://gitlab.com/gitlab-org/gitlab-ce/issues/21896

See merge request !6233

Allow compare merge request versions

## What does this MR do?

Add new functionality to the merge request page. It allows you easily compare merge request versions in one click.  

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

To improve code review experience. 

## Screenshots (if relevant)

See discussion

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] ~~API support added~~
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

https://gitlab.com/gitlab-org/gitlab-ce/issues/13570

See merge request !6127

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Enable rspec documentation formatter and color output

Current rspec just outputs a `=` as each test runs. This enables the documentation formatter and color output to make it easier to know what is going on with each spec.

See merge request !5924

Merge branch '21109-discussion-resolve-runs-a-single-update-query-per-note-but-should-run-a-single-update-query-for-all-notes-instead' into 'master'

Optimize discussion notes resolving and unresolving

## What does this MR do?

Optimize discussion notes resolving and unresolving

## Are there points in the code the reviewer needs to double check?

Some changes had to be made to the discussion spec to account for the fact that notes are not  individually updated now. I only focused on adapting them for the purpose of the regression fix, but admittedly they could be further improved in readability.

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #21109

See merge request !6141

Allow updating a branch by multiple commits

In https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6130 we made
Repository#commit_with_hooks a bit too strict; it only allowed
updating a branch by one commit. It turns out there is a feature in
GitLab Enterprise Edition where we update by multiple commits.

This change makes that possible, adds tests, and renames the method to
the more appropriate 'update_branch_with_hooks'.

See merge request !6246

Update CHANGELOG entries for 8.11.5.



See merge request !6255

Change update interval of runners when trying to preserve contacted_at

See merge request !6126

Rename `gl_user_id` to `gitlab_user_id` in importer classes

Closes #21772

See merge request !6254

Fix DB schema to match latest migration

See merge request !6256

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

I've also removed some duplicates from 8.11.4.

Fix randomly failing specs (possibly caused by DatabaseCleaner)

## What does this MR do?

This MR ensures that DatabaseCleaner.clean runs AFTER Capybara's cleanup. This is needed because it *seems* like database is being truncated before capybara session ends, which leads to `undefined method ... for nil:NilClass` exceptions causing tests to randomly fail.

## Are there points in the code the reviewer needs to double check?

Failing spec is https://gitlab.com/gitlab-org/gitlab-ce/blob/master/spec/features/boards/boards_spec.rb. Here are some examples of failed builds: 

- https://gitlab.com/gitlab-org/gitlab-ce/builds/3352437
- https://gitlab.com/certik/gitlab-ce/builds/3359940
- https://gitlab.com/gitlab-org/gitlab-ee/builds/3365914

## Why was this MR needed?

I've noticed that many branches suffer from random failures and it's not very comfortable for big test suite. Re-running builds until they pass is not a solution so I tried to come up with a fix. Unfortunately I can't be 100% sure about this fix (flaky test is always green on my local environment, so I can't be sure if green build on CI is false-positive or not), but if database is really being cleaned too early (which is clearly proved by logs provided here https://gitlab.com/gitlab-org/gitlab-ce/issues/21841#note_14926675 then it's very likely that this fix will help to get rid of random failures.

Also it's officially recommended in DatabaseCleaner README to use `append_after` hook instead of just `after` because of the way RSpec runs after hooks (in reverse order):

> It's also recommended to use append_after to ensure DatabaseCleaner.clean runs after the after-test cleanup capybara/rspec installs.

([source](https://github.com/DatabaseCleaner/database_cleaner#rspec-with-capybara-example))

## What are the relevant issue numbers?

#21197

See merge request !6198

Added cron to prune events older than 12 months.

See merge request !6200

Fix layout issues with blame table

## What does this MR do?

Fixes layout issues with the blame before. Previously the content would expanded out of the table making it look ugly!

## Screenshots (if relevant)

![Screen_Shot_2016-09-06_at_10.36.17](/uploads/719fc7cdf909b18afbe8afafbae7d99a/Screen_Shot_2016-09-06_at_10.36.17.png)

## What are the relevant issue numbers?

Closes #21216

See merge request !6218

Refactor sidebar logic for more predictable behavior

## What does this MR do?

Fixes a few bugs with the sidebar and "pin" functionality:

1. Pinned state would get reset when loading a page with a viewport smaller than 1024px (#19183)
2. Toggle buttons could occasionally end up in an invalid state in which the toggle is hidden from view at the same time the sidebar is collapsed.
    ![2016-09-03-09.39.07](/uploads/75d9a836ab58aae9f89f38cc29e90bbd/2016-09-03-09.39.07.gif)

3. Clicking outside the sidebar to trigger 'collapse' when below the 1024px breakpoint would work only if not pinned, even though pin status should only effect the sidebar above the 1024px breakpoint.
4. Code confusing with no single source of truth for the state of the sidebar.  Sometimes pinned state is inferred from the cookie, sometimes from the DOM.  Code to handle these functions was confusingly split across both `sidebar.js` and `application.js` for no apparent reason.

I've created a singleton ES6 class to handle the sidebar DOM manipulations, using the properties `isExpanded` and `isPinned` as the canonical state and providing a `renderState` method to sync the DOM with this state whenever it needs updating.  This avoids the possibility of invalid states caused by reliance on jQuery `toggleClass()` methods and makes the code much more readable/maintainable.

## Are there points in the code the reviewer needs to double check?

It is a substantial rewrite, so I could use another set of eyes to make sure nothing was left behind from the original implementation.

## Why was this MR needed?

I initially intended to just fix #19183 by modifying the code in place, but it proved to be a difficult mess and rather than add to the technical debt it made sense to write a more readable implementation of the sidebar functionality.

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [ ] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #19183

See merge request !6169

update rouge to 2.0.6

## What does this MR do?

Bumps rouge to 2.0.6

## Are there points in the code the reviewer needs to double check?

Changelog here: https://github.com/jneen/rouge/blob/master/CHANGELOG.md#version-206-2016-09-07


## Why was this MR needed?

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

See merge request !6251

Fix project settings field

fixes #21821

See merge request !6185

Add textarea autoresize after comment

## What does this MR do?
Adds an autoresize after a comment is posted

## Are there points in the code the reviewer needs to double check?
Shouldn't be

## Why was this MR needed?
To keep the UI consistent (the same as if you were to refresh it)

## Screenshots (if relevant)
Before:
![IyCczzXfaf](/uploads/2229bad47e3f3821f1efaa6868a52025/IyCczzXfaf.gif)

After:
![E6O0kRBrJq](/uploads/4aec6b436ff172ba281c2c2a4481906d/E6O0kRBrJq.gif)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
Closes #21667

See merge request !6152

Fix contributions calendar month label truncation

## What does this MR do?
Expands the width of the contributions calendar by 3px when the last column is a new month to prevent the month label from being truncated

## Are there points in the code the reviewer needs to double check?
Shouldn't be

## Why was this MR needed?
Fixes an existing UI issue

## What are the relevant issue numbers?
Closes #20844 

## Screenshots (if relevant)
Before:
![Screen_Shot_2016-08-11_at_1.24.47_PM](/uploads/682a616a335fffd610342037c41ab9ad/Screen_Shot_2016-08-11_at_1.24.47_PM.png)

After:
![Screen_Shot_2016-08-11_at_1.24.13_PM](/uploads/6e7aa12dd9e3a2c570f1327aaef09fc7/Screen_Shot_2016-08-11_at_1.24.13_PM.png)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5779

sync sidebar DOM state on page:change to minimize split-second appearance of the sidebar in certain situations