Refactor project routing

## What does this MR do?

Refactor project routing: 

* split on multiple files
* improve routing order


## Why was this MR needed?

It makes it easier to maintain and modify project routing

## What are the relevant issue numbers?

Extracted from https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7121

See merge request !7329

Refactor namespace regex

Reuse existing namespace regex constant in routing

See merge request !7336

Set default Sidekiq retries to 3

See merge request !7294

Refactor group routing

## What does this MR do?

Refactor group routing: 
* separate controller actions from nested resources
* prepare group routing for nested namespaces support

## Why was this MR needed?

So when we introduce nested groups support we need to only change `:id` to `*id`

## What are the relevant issue numbers?

Extracted from https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7121

See merge request !7328

Bump omniauth-gitlab to 1.0.2 to fix incompatibility with omniauth-oauth2

As noted in gitlab-com/support-forum#1270, omniauth-gitlab fails if omniauth-oauth2 is bumped to 1.4.0, OAuth2 quietly fails due to https://github.com/linchus/omniauth-gitlab/issues/10:

```
21:26:04 rails-web.1             | I, [2016-11-07T21:26:04.245007 #56637]  INFO -- omniauth: (gitlab) Callback phase initiated.
21:26:05 rails-web.1             | E, [2016-11-07T21:26:05.068009 #56637] ERROR -- omniauth: (gitlab) Authentication failure! invalid_credentials: OAuth2::Error, invalid_grant: The provided authorization grant is invalid, expired, revoked, does not match the redirection URI used in the authorization request, or was issued to another client.
```

This was fixed and discussed here: 
* https://github.com/linchus/omniauth-gitlab/commit/26c47e55396205fab8439363c98136d0fde797f3
* https://github.com/linchus/omniauth-gitlab/issues/10

Bumping this version to 1.0.2 will ensure future compatibility.

See merge request !7348

Use separate email-friendly token for incoming email

See merge request !5914

Fixed todos empty state when filtering

Closes #24127

See merge request !7334

Fix project index page

See merge request !7331

API: Return 400 when creating a systemhook fails

Closes #23335

See merge request !7350

Network page appear with an error message when entering nonexistent git revision

Closes #2362

See merge request !7172

Moved if statements around in view

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Closes gitlab-com/support-forum#1270

Replace trigger with the new ID of the docs project

Now that the old docs site is deprecated in
favor of https://gitlab.com/gitlab-com/gitlab-docs

See merge request !7343

[ci skip]

17492 Update link color for more accessible contrast

## What does this MR do?
Improves contrast of links to pass accessibility contrast checker http://webaim.org/resources/contrastchecker/

## Screenshots (if relevant)
Before:
![Screen_Shot_2016-11-07_at_11.09.44_AM](/uploads/233c53cd81436a00f0cc7f826ca900df/Screen_Shot_2016-11-07_at_11.09.44_AM.png)
After:
![Screen_Shot_2016-11-07_at_11.09.22_AM](/uploads/698ac990d61434893709a3cea78896d9/Screen_Shot_2016-11-07_at_11.09.22_AM.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?


Closes #17492

See merge request !7340

Rewritten spinach git_blame tests to RSpec feature tests

Part of #23036. This MR contains 'git blame' feature tests rewritten in RSpec.
 
See merge request !7197

Use the Gitlab Workhorse HTTP header in the admin dashboard

Fixes issue #21664 where the GitLab Workhorse version displayed within the Admin Area was not correct for installations from source.

See merge request !7332

Closes #24127

Upgrade redis-rails from 4.0.0 to 5.0.1.

This updates redis-rails to 5.0.1 along with its dependencies. I helped upgrade redis-actionpack so it would work with both Rails 4.2 and 5.0 in the same version.

Unfortunately none of the gems have Changelogs :/

- redis-rails: https://github.com/redis-store/redis-rails
- redis-actionpack: https://github.com/redis-store/redis-actionpack
- redis-activesupport: https://github.com/redis-store/redis-activesupport
- redis-rack: https://github.com/redis-store/redis-rack
- redis-store: https://github.com/redis-store/redis-store

Working toward #14286.

See merge request !7291

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Expose Label id to API

Closes #23448

See merge request !7275

reactivates all tests and writes more tests for it

email token be reset

Processing Commits Using Sidekiq

This moves the code  of `GitPushService#process_commit_messages` into a separate Sidekiq worker. This allows processing of commits to happen in parallel, speeding up the process. See the individual commit (messages) for more information.

Part of https://gitlab.com/gitlab-org/gitlab-ce/issues/15463

See merge request !6802

Add missing security specs for raw snippet access

## What does this MR do?
It extends the project snippets access security specs to cover raw snippet paths as well.

When I was researching snippets for !7256, I noticed that specs existed for the HTML show view of project snippets but not the raw view. Seeing as this is a spec that is checking for access regressions on places where sensitive information might be kept, I thought it would be a good idea to cover the raw snippets access too.

To balance out the karma of adding in extra tests I also changed the tests to all use an `empty_project` spec.

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

With the aim of making the specs easier to read, I restructured some of them to use context blocks for each type of snippet.

I've used the same access rights defined for the show snippet paths for the raw snippet access. 

## Why was this MR needed?

To catch security regressions on raw snippet access for projects.

## Screenshots (if relevant)

## 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
  - [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?

See merge request !7300

Signed-off-by: Rémy Coutable <remy@rymai.me>

* split on multiple files
* improve routing order
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Fixing rubocop violations

Relocated git_blame spec and fixed styling issue

Rewritten spinach git_blame tests to rspec feature tests

Fixing rubocop violations

Relocated git_blame spec and fixed styling issue

Rewritten spinach git_blame tests to rspec feature tests

Fixing rubocop violations

Rewritten spinach git_blame tests to rspec feature tests

Fixing rubocop violations

Rewritten spinach git_blame tests to rspec feature tests

Fixing rubocop violations

Relocated git_blame spec and fixed styling issue

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

[e44da1c] Add Label API expected keys to tests

[ac929c8] Update Label API documentation

* separate controller actions from nested resources
* prepare group routing for nested namespaces support
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Use `git update-ref --stdin -z` to speed up TestEnv.set_repo_refs

See merge request !7283

Use more than one kind of Git garbage collection

Replaces https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6588 by @jacobvosmaer to get the builds to pass :)

Closes #22729

See merge request !7321