Remove leftover references to coffeescript from comments and docs.

I was looking at the front-end helper spec and noticed some outdated coffeescript refs in it. So I figured it wouldn't hurt to take a few minutes and remove all the coffeescript references in CE that we don't need anymore. 

I didn't touch any coffeescript references that could potentially break anything. Just docs and code comments.

- [x] All builds are passing

See merge request !7151

Fix project features default values

closes #23242

See merge request !7181

Correct padding and alignment for reaction buttons

## What does this MR do?
Fixes padding and alignment for reaction buttons on issues.

## Screenshots (if relevant)

### Before
![img](https://gitlab.com/gitlab-org/gitlab-ce/uploads/ae788883aca84799fca9cd23f8e16f28/image.png)
![img](https://gitlab.com/gitlab-org/gitlab-ce/uploads/b2f5aa45dbb4899f054f839bd9046bb6/image.png)

### After
![Screen_Shot_2016-10-28_at_3.56.03_PM](/uploads/0b1affed448f6ec24fa56e7800daf753/Screen_Shot_2016-10-28_at_3.56.03_PM.png)
![Screen_Shot_2016-10-28_at_3.56.09_PM](/uploads/311bb59dc6eea8cd124232ebe647b5ef/Screen_Shot_2016-10-28_at_3.56.09_PM.png)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG.md) 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 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?


Closes #23918

See merge request !7182

Fix relative links in Markdown wiki when displayed in "Project" tab

Refers to #23806

See merge request !7218

Implement CreateProjectMembers service to make controller thin

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/23566

See merge request !7170

Add a link to the Issue Boards API in main README

See merge request !7221

[ci skip]

Blacklist the OSL 3.0 license

See merge request !7171

Do not show tooltip for active element

## What does this MR do?

Change Bootstrap's default for tooltips to display them only when hovering and not for the active element.

See also here: https://getbootstrap.com/javascript/#tooltips-options

## Screenshots

### Before

![before](/uploads/c5b7bd9eba07ca61bfa5ba014d08dd1a/before.webm)

### After

![after](/uploads/d8c4a69e5a6797d8d26ab92cb96fcb2d/after.webm)

## What are the relevant issue numbers?

Closes #23794

See merge request !7105

Fix Markdown styling inside reference links

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/18096.

Based off https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6609.

See merge request !7169

Fix project visibility level link

Fix wrong syntax for link generation.

See merge request !7201

Update tags.md

See merge request !7202

Fixes: https://gitlab.com/gitlab-org/gitlab-ce/issues/18096

Refers to #23806.

Optimize group labels page

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/23684

Closes https://gitlab.com/gitlab-org/gitlab-ee/issues/1148

See merge request !7123

Updated positioning of copy file path button in diffs

## What does this MR do?

Updated the positioning of the copy file path button in diffs.

## Screenshots (if relevant)

![Screen_Shot_2016-10-31_at_16.53.24](/uploads/53de39ce550855f86b90d2d9fc227f95/Screen_Shot_2016-10-31_at_16.53.24.png)

## What are the relevant issue numbers?

Closes #23591

See merge request !7203

GrapeDSL for branches endpoints

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

See merge request !6630

Add ES array methods as cause of Phantom.js errors.

## What does this MR do?

Adds another example of something that causes a common error in JavaScript testing to the frontend dev docs.

See merge request !7102

Resolve "Clean up commit meta info view"

Updates commit page design   
Before:   
![Screen_Shot_2016-10-19_at_10.20.10_AM](/uploads/8737a9db01bffc019d8b2c71a943024b/Screen_Shot_2016-10-19_at_10.20.10_AM.png)
After:   
![Screen_Shot_2016-10-19_at_10.20.01_AM](/uploads/716cb902bd20dedc705a8f81f6536736/Screen_Shot_2016-10-19_at_10.20.01_AM.png)
![Screen_Shot_2016-10-19_at_10.27.01_AM](/uploads/4228575f50990a88bc828037d8fb99f2/Screen_Shot_2016-10-19_at_10.27.01_AM.png)
Closes #20892

See merge request !6994

[ci skip]
Signed-off-by: Rémy Coutable <remy@rymai.me>

Closes #23591

Fix builds tab visibility

closes #23951

See merge request !7178