Make milestone labels in labels tab similar to that of the labels page

I realized that some of the changes for the labels page was not reflecting in the labels list in milestone page.

## Desktop
![Screen_Shot_2016-04-11_at_4.25.36_PM](/uploads/e21f3c5a9187fe32472e796171781b5d/Screen_Shot_2016-04-11_at_4.25.36_PM.png)

## Mobile
![Screen_Shot_2016-04-11_at_4.26.47_PM](/uploads/5c9f75ca0938fc30ab47c5520215f692/Screen_Shot_2016-04-11_at_4.26.47_PM.png)


See merge request !3658

API: Subscribe and unsubscribe from issues and merge requests

* Closes #6024 

This MR is based on !3611, which must be merged first.


See merge request !3615

Fix high CPU usage when PostReceive receives refs/merge-requests/<id>

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12661


See merge request !3651

API: Star and unstar a project

Add two new endpoints `POST /projects/:id/star` and `POST /projects/:id/unstar` to star and unstar a project.

* Closes #12739


See merge request !3578

Fix bug causing comment form in issue to submit twice when CTRL+Enter is pressed twice



See merge request !3655

Remove Bootstrap Carousel

The Bootstrap carousel module is used for image carousels, and we don't
use it anywhere on the site.

Fixes #14670.

See merge request !3624

Instrument the HousekeepingService class

I'm starting with instrumenting this class as mentioned in https://gitlab.com/gitlab-org/gitlab-ce/issues/15094#note_4796278.

See merge request !3701

Fix Grafana docs and link from Influx page

Fixing images and adding links to Influx docs, as suggested by @sytses 

See merge request !3702

This allows us to track how much time is spent in updating the
"pushes_since_gc" column as well as the time needed to obtain the lease.

Fixed not being able to filter by any or no labels

Brings back the options to filter by any or no label

Closes #15008 

![Screen_Shot_2016-04-07_at_11.26.41](/uploads/20d949b19f537d830118532e1d44feb7/Screen_Shot_2016-04-07_at_11.26.41.png)

See merge request !3589

Allow Omniauth providers to be marked as external

Related to #4009 

With this MR we will be able to allow the user to set which Omniauth Providers they would like to have as external. All users login in via these providers will be marked as external, even if they already had an account before. If the provider is removed form the list of external providers, the users will be marked as internal at their next login.

MR for Omnibus: gitlab-org/omnibus-gitlab!727

/cc @dblessing @DouweM 

See merge request !3657

Move RepositoryArchiveCacheWorker to sidekiq-cron

Closes #15105

See merge request !3663

Add `Gitlab.com?` method

To be used as a feature flag for GitLab.com-only features, such as
welcome emails.

We will be careful to only use this to disable features or functionality
that do not make sense for any installations that aren't GitLab.com. We
will not use this to restrict features from other installations or keep
them "exclusive" to GitLab.com.

See merge request !3682

(doc) fix typo to ssh keys doc url

API: Return 404 if user does not have access to group

Closes #15185 

After !3587 is merged, I'll update this one to also fix the return code of the tests in !3587.

See merge request !3683

API: Ability to move an issue

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/14741

See merge request !3593

improve formatting



See merge request !3688

Added ability to add custom tags to transactions

cc @pcarranza 

See merge request !3674

Adjust the default trusted_proxies to only include localhost

And also allow other trusted proxies to be added from the config.yml.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/3538

Omnibus config: https://gitlab.com/gitlab-org/omnibus-gitlab/issues/1208

See merge request !3524

Tie example config to JIRA screenshot

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15203

See merge request !3693

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15203

One use case for this is manually setting the "action" tag for Grape API
calls. Due to Grape running blocks there are no human readable method
names that can be used for the "action" tag, thus we have to set these
manually on a case by case basis.

Allow to close invalid merge request

fixes #15044

See merge request !3664

Docs for the new branch button

[ci-skip]

Closes #3886 

@axil Could you check this and make sure this is up to your standards?



See merge request !3425

Fix repository cache invalidation issue when project is recreated with an empty repo

See merge request !3692