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

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

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: Rémy Coutable <remy@rymai.me>

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

The target branch of a merge request has to be a branch in the project
for which the merge request is submitted. When a branch changes in a fork,
it does not make sense to reload diffs of merge requests in the upstream
project that use the same branch name as the target branch.
Please note that it does make sense to reload diffs when the source branch
changes.