Use default btn styling for Housekeeping button on projects settings page

Changes the Housekeeping button styling on the project settings page from ```btn-save``` to ```btn-default```

**BEFORE:** ![Screen_Shot_2016-12-06_at_12_51_42_PM](/uploads/1b1c8a26eead025062e2c98d9d0f4286/Screen_Shot_2016-12-06_at_12_51_42_PM.png)

**AFTER:** ![Screen_Shot_2016-12-06_at_12_51_57_PM](/uploads/9e7937af4a058fa1aa8b45653dbad3ee/Screen_Shot_2016-12-06_at_12_51_57_PM.png)

Closes #25324 
cc: @awhildy

See merge request !7959

fix display hook error message

## What does this MR do?

Fix hook error message display.  

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

Probably Hook will return the plain multi line text.  It is better `pre` tag than `h4`.  
I thought of another good looking display, but I did not come up with it. 😓 

## Why was this MR needed?

When the hook returns an STDERR, "Merge in progress" button spinning forever. Due to javascript's error.  

## Screenshots (if relevant)

When update hook returns an error like

```
XXXXXXXX

YYYYYYYY
ZZZZZZZZ
```

![screen_shot](/uploads/8dac77972a309dfcb72c741dffbd7270/screen_shot.png)

## What are the relevant issue numbers?

Closes #24020

See merge request !7775

Stop replacing `$your_email` with the user's email in the `/help` pages

See merge request !8014

Remove 'Leave Project' and 'Leave Group' from settings dropdowns

## What does this MR do?

Removes `Leave Project` and `Leave Group` from the settings dropdown.

Adds it to the `views/shared/members/access_request_buttons.html.haml`.

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

## Why was this MR needed?

## Screenshots (if relevant)

![Screen_Shot_2016-11-19_at_15.34.26](/uploads/5c66a025513b4780a9e881f0036381e4/Screen_Shot_2016-11-19_at_15.34.26.png)
![Screen_Shot_2016-11-19_at_15.35.29](/uploads/ed74a5dfe982cf65bb49c0c4fb307061/Screen_Shot_2016-11-19_at_15.35.29.png)

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) 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
  - [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 it does - 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 #23305

See merge request !7600

Use gitlab-workhose 1.1.1

Change CI API rate limiting behavior.

Will make a separate MR for 8-14-stable because that version lacks the workhorse install rake task.

See merge request !7990

Updates the font weight of button styles because of the change to system fonts

## What does this MR do?

Updates the font weight of button styles because of the change to system fonts

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

## Why was this MR needed?

Because of the change to system fonts the font weight for buttons needed to be toned down a bit.

Seems only buttons styles were affected.

## Screenshots (if relevant)

left = result

![image](/uploads/c75868dca76561cafd559fb721be0601/image.png)

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) 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 it does - 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?


cc: @cperessini

See merge request !8012

Updated members dropdowns

## What does this MR do?

EE has different dropdowns to allow for group LDAP members to be overridden, this ports the dropdown changes over to reduce conflicts.

## Screenshots (if relevant)

![Screen_Shot_2016-12-07_at_15.28.20](/uploads/6cb6def34015b024dc878aa3b99be4a0/Screen_Shot_2016-12-07_at_15.28.20.png)

See merge request !7974

Use a single query in Projects::ProjectMembersController to fetch members

See merge request !7997

Update "Installation from source" guide for 8.15.0

Following the steps from https://gitlab.com/gitlab-org/release-tools/blob/master/doc/release-candidates.md#creating-rc1.

See merge request !8015

Resolve "Provide SVG as a prop instead of hiding and copy them in environments table"

## What does this MR do?
- Provides SVG as a prop instead of manually manipulate the DOM to show it 
- Uniforms all props names in environments related components, 3 formats were being used and it was error prone
- Adds tests for the new SVG props.

## Why was this MR needed?
Technical debt.

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) 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
  - [ ] 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 it does - 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 #25374

See merge request !7992

The `$your_email` was removed from the SSH doc.
Signed-off-by: NRémy Coutable <remy@rymai.me>

Displays milestone remaining days only when it's present

See merge request !7998

Do not reload diff for merge request made from fork when target branch in fork is updated

Closes #25263

See merge request !7973

API: Ability to remove source branch

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/23577

See merge request !7804

Fix comments tab disappearing

Fixes #25272

See merge request !7913

Render SVG images in notes

Closes #24937 

See merge request !7747

Update JIRA troubleshoot documentation

closes #25152

See merge request !7977

Improvements to setting up SSH documentation

## What does this MR do?

Improves the documentation article on setting up SSH. 

* Added introduction
* Added additional explanations
* Added sub headings
* Moved sections around
* Added section about generating an SSH key pair on Windows with PuttyGen (will be expanded further in future)

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/24708

See merge request !6571

[ci skip]