Copy logic from `Devise::Models::Lockable#valid_for_authentication?`, as
our custom login flow with two pages doesn't call this method. This will
increment the failed login counter, and lock the user's account once
they exceed the number of failed attempts.

Also ensure that users who are locked can't continue to submit 2FA
codes.

GrapeDSL for Namespace endpoint

No changelog item as it doesn't change behaviour

Cherry-picked from !6330

See merge request !6632

Fix issues importing services via Import/Export

Prevents errors when initialising services that do not have any properties set yet - case that could happen when importing projects.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/22891

See merge request !6667

Add Container Registry on/off status to admin area

## What are the relevant issue numbers?

Closes #22805

See merge request !6638

Remove SCSS rules for short hex chars.

## What does this MR do?
Remove CSS hex shorthands linter
## Are there points in the code the reviewer needs to double check?
That I did it right. 
## Why was this MR needed?
To remove SCSS linter for hex shorthands
## 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?
Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/22920

cc @connorshea

See merge request !6663

Changed mr widget build status to pipeline status

## What does this MR do?

Changed mr widget build status to pipeline status with pipeline id, with a link to the pipeline.

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

Do we want the link to the pipeline?

/cc @dimitrieh 

## Screenshots (if relevant)

![Screen_Shot_2016-09-14_at_02.42.23](/uploads/94a860361ab70eccf966e519764c6ec5/Screen_Shot_2016-09-14_at_02.42.23.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?

Closes #22006

See merge request !6335

Fix tooltip text when Copy to cliboard is clicked

## What does this MR do?

Fixes #22022 to change tooltip text to "Copied!" when the "Copy to clipboard" button is clicked.

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

Line 29 in app/assets/javascripts/copy_to_clipboard.js

## Why was this MR needed?

There was a regression that prevents tooltip change on button click for Copy to clipboard.

## 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?

Closes #22022

See merge request !6294

Enable Lint/StringConversionInInterpolation cop and autocorrect offenses



See merge request !6654

Display the on/off icon under the "Features" section of the admin area
for the Container Registry.

Closes !22805

Changed Slack service user referencing from full name to username

Closes #22737

See merge request !6624

Add configurable email subject suffix

## Why was this MR needed?

I noticed that there is a commit 44ab156e 3 years ago which removes email subject prefix

actually we do need an special part of the email subject which makes the email subject easy to identify

we just need to make it configurable rather than remove it.

See merge request !6172

Log sidekiq arguments as json

Logging the sidekiq job arguments as a ruby literal structure 
is akward. Specially when parsing the logs.

JSON is a standar format.



See merge request !3735

Resolve "Task List Checkbox Alignment"

## What does this MR do?

Replace the unmaintained `task_list` gem with the `deckar01-task_list` fork

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

 - I had to pin some dependencies in the fork to support `ruby < 2.2`, which added new version restrictions for 2 existing modules.
 - I triggered a build after I removed the patch to show the test passed with the new gem, then I removed the test, because this behavior is tested in the gem's repo now.

## Why was this MR needed?

 - The `task_list` patch was added with a comment that said it should be removed when merged upstream, but the repo got archived, so an upstream patch requires a fork.
 - #22470 can't be patched without warnings due to the way `task_list` uses Ruby constants.
 - There are additional outstanding `task_list` bugs that can be fixed once we switch to a fork.

## What are the relevant issue numbers?

 - #22466 
 - #22470
 - !6487

See merge request !6625

GrapeDSL for Award Emoji endpoints

Cherry-picked from !6330

See merge request !6629

Enable Import/Export for non-admin users

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/21315

Related https://gitlab.com/gitlab-org/gitlab-ce/issues/20857 and https://gitlab.com/gitlab-org/gitlab-ce/issues/20821/

See merge request !6080

Use custom Ruby images to test builds

It allows us to remove redundant steps of installing required dependencies for every build.


See merge request !4506

Better empty state for Groups view.

Implemented @hazelyang's [awesome design](https://gitlab.com/gitlab-org/gitlab-ce/uploads/9141470ed121f137a4074ae4e12c449c/groups-empty.png) for empty group views.

Fixes #20829 


### Design
![https://gitlab.com/gitlab-org/gitlab-ce/uploads/9141470ed121f137a4074ae4e12c449c/groups-empty.png](https://gitlab.com/gitlab-org/gitlab-ce/uploads/9141470ed121f137a4074ae4e12c449c/groups-empty.png)


### Screenshots
![Screen_Shot_2016-09-28_at_13.43.35](/uploads/e2ab668a412596205deb67c97af78a1d/Screen_Shot_2016-09-28_at_13.43.35.png)

![Screen_Shot_2016-09-28_at_13.44.54](/uploads/c4301166f353f0ee198aecdc46cdfe66/Screen_Shot_2016-09-28_at_13.44.54.png)

![Screen_Shot_2016-09-28_at_13.46.10](/uploads/92024e866871969ec7a28db4b8e87220/Screen_Shot_2016-09-28_at_13.46.10.png)

![Screen_Shot_2016-09-28_at_13.46.20](/uploads/f1b515c7aa09d06e80a419d98ff76fd6/Screen_Shot_2016-09-28_at_13.46.20.png)

![Screen_Shot_2016-09-28_at_13.46.34](/uploads/76cdd5f0e9d3c59d017df26172f7dd4d/Screen_Shot_2016-09-28_at_13.46.34.png)

See merge request !6566

Convert "SSH Keys" Spinach features to RSpec

See merge request !6639

GrapeDSL for Keys endpoint

No changelog item as it doesn't change behaviour
Cherry-picket from !6330

See merge request !6631

Update GITLAB_SHELL_VERSION to 3.6.3

Because VERSION at the gitlab-shell v3.6.2 tag was still 3.6.1: https://gitlab.com/gitlab-org/gitlab-shell/blob/v3.6.2/VERSION (my bad!)

VERSION at the v3.6.3 tag is now 3.6.3: https://gitlab.com/gitlab-org/gitlab-shell/blob/v3.6.3/VERSION

See merge request !6621

Fix broken left sidebar navigation

Sidebar navigation is broken and it's introduced in !6627. Sidebar pin and hamburger icons were `a` tag before with `#` link on them. That was the main reason why page jumps to top. !6627 was trying to prevent default action but it interferes with the navigation links. I don't want to tweak event listeners for sidebar, instead I just replaced `a` elements with `div` because I think there is no point to have them as `a`.

/cc @dzaporozhets @jschatz1 

PS: This MR basically reverts !6627. I don't want to add another revert commit instead I reverted it in my editor and committed.

See merge request !6648

Add a /wip slash command to toggle the 'WIP' prefix in the MR title

## Why was this MR needed?

As explained in #21225, it prevents you from having to click through the entire edit form just to mark an MR as WIP.

Closes #21225

See merge request !6259