Refine CI Statuses

## What does this MR do?

This MR introduces classes for each relevant CI status.

## What are the relevant issue numbers?

Closes #24273

See merge request !7889

Use `--extended-regexp` in lint-doc for compatibility with Darwin grep

Now it should work on all platforms.

See merge request !7943

GLM shorthand reference for projects from the same namespace

Closes #21679

See merge request !7255

Authorize users into imported GitLab project

https://gitlab.com/gitlab-com/support-forum/issues/1313

See merge request !7936

Fixed MR widget content wrapping for XS viewports

Centers the "Accept Merge Request" button within the MR widget (and adds a bit of right/left padding) for viewports smaller than 768px.

BEFORE:
![Screen_Shot_2016-12-02_at_8_53_01_AM](/uploads/fcdae5302a1407090483dd3cff868c51/Screen_Shot_2016-12-02_at_8_53_01_AM.png)

AFTER:
![Screen_Shot_2016-12-02_at_9_43_37_AM](/uploads/f7d1dce082b79d263f05cea3c90e870a/Screen_Shot_2016-12-02_at_9_43_37_AM.png)

cc: @markglenfletcher @annabeldunstone 
Closes #25202

See merge request !7900

Ensure state param has a valid value when filtering issuables.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/25064

This fix makes sure we only call safe methods on issuable when filtering by state.

See merge request !2038

Document the public Project API and document `GET /projects/:id/users`

Documentation was not updated in !7843. Also the `GET /projects/:id/users` endpoint was not documented at all!

See merge request !7897

Remove unused errors css

`.error-page` isn't being used anywhere as far as I can see so I removed it

See merge request !7933

Remove unused votes.scss

`.votes-inline` isn't being used anywhere

See merge request !7934

NIGNX -> Nginx

This shouldn't be in all caps, and it should be spelled correctly!

See merge request !7929

It's secret variables, not secure

See merge request !7939

[ci skip]

Refactor CI variables docs

See merge request !7751

[ci skip]

Make the 'Group projects' links clickable in the admin screens

## What does this MR do?
This MR makes the group links within the 'users' section of the admin interface clickable. Currently, to view the details of groups a user is a member of, you have to go back to the 'groups' tab (which isn't ideal).

## Are there points in the code the reviewer needs to double check?
No

## Why was this MR needed?
It's a UX improvement - it saves going back to the 'groups' a user is a member of and then clicking the group to view the group details.

## Screenshots (if relevant)

### Before
![Screenshot_from_2016-11-21_14-25-01](/uploads/2a6b75efd4c700e5760c64f0db17e847/Screenshot_from_2016-11-21_14-25-01.png)

### After
![Screenshot_from_2016-11-21_14-24-42](/uploads/9be288c1d9e4cf818c96e11e24790860/Screenshot_from_2016-11-21_14-24-42.png)

## Does this MR meet the acceptance criteria?

- [ ] [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?

See merge request !7620

Document button secondary states

## What does this MR do?
Document the changes from #24145 and !7797.

It also updates the icons and color section in the basics page.

## Does this MR meet the acceptance criteria?

- [ ] [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?
#24145

cc @awhildy

See merge request !7924

Describe hover, focus and active states for primary and secondary
buttons.

Organized the icons section in a table. Replaced images for icons
so they are all the same size.

Organized the color section in a table. Replaced the images with
new ones so the table would have a more manageable size. Updated
the values for some colors to show the $color-light shade.

Remove commented sections

Remove `db/schema.rb`

Add db/schema.rb from origin/master

Fix typos

Added element extensions spec for .matches and .closest

## What does this MR do?

Adds tests for `Element.prototype.matches` and `Element.prototype.closest`.

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

## Why was this MR needed?

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [ ] [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?

See merge request !7755

Refactor create service spec

## What does this MR do?
Use let instead instance variables to cache create user operation.

Union some example into one.

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

## Why was this MR needed?
Time before: 1 minute 11.81 seconds

Time after: 52.47 seconds

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- n/a [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- n/a API support added
- Tests
  - n/a 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?

See merge request !7609

Fixed top margin for Builds page status header information

Adds top margin for the Build Status content area for screens smaller than 768px. Especially needed when the text content wraps onto a third line.

![Untitled-1](/uploads/57a0a58f1fe647cd2d0dbb8849621340/Untitled-1.jpg)

cc: @filipa @ClemMakesApps 
Closes #25221 

See merge request !7917

Use pry-byebug instead byebug

See merge request !7925

Update merge_requests.scss

Update merge_requests.scss to use padding shorthand

Removed padding from Accept Merge Request button

This shouldn't be in all caps, and it should be spelled correctly!

Reduce base font sizes across app by 1px

Looking at other websites that use system fonts, the default seems to be `14px`. We currently use `15px` which feels a little too big at the moment (in my opinion). This is just an idea so feel free to close it @awhildy 😄    
Before:   
![Screen_Shot_2016-12-02_at_1.46.25_PM](/uploads/4e287d3e66b1fe1dbac9999978594546/Screen_Shot_2016-12-02_at_1.46.25_PM.png)
After:   
![Screen_Shot_2016-12-02_at_1.46.02_PM](/uploads/09aed0952c25df214e8e5fb1404d6f4f/Screen_Shot_2016-12-02_at_1.46.02_PM.png)

See merge request !7905

change the date label to match the date used

Closes #1608

See merge request !7860