Add ability to push to remote repositories

Closes #116 

See merge request !249

* Use Rugged filters to work with local/remote branches.
* Rename Project#remote_mirror? to Project#has_remote_mirror?
* Use delegate pattern for Repository#push_remote_branches and Repository#delete_remote_branches
* Make Repository#remote_tags return Gitlab::Git::Tag objects.
* Refactor Repository#remote_branches
* Rename Repository#push_branches to Repository#push_remote_branches
* Made other small refactors to views and specs.
* Make encrypted_credentials column size bigger.
  This was giving problems with MySql for large passwords.
* Refactor for UpdateRemoteMirrorService spec so we no longer
  harcode the branch names and specs are not broken after `gitlab-test`
  project is updated.

* Also fixed couple of small bugs introduced with last changes

* Also addressed feedback from https://gitlab.com/gitlab-org/gitlab-ee/commit/fcbfe56207f64da07deb7f3a8cbdcd505069edbd

* Now #url= and #url always handle the full URL, encryption is done transparently
* #safe_url was added for future purposes
* Little refactor for UpdateRemoteMirrorService

* Also added small fix for the scenario when the remote repo is empty
 and does not have tags.

* Add the ability to skip tags when fetching a remote repo.
  See: https://gitlab.com/gitlab-org/gitlab-shell/merge_requests/46

Merge branch 'regression-ldap-group-synchronization-is-broken-for-our-company-s-ldap-with-gitlab-8-6-442' into 'master'

Fix LDAP group sync regression for groups with member value `uid=<username>`

Closes #442 

See merge request !335

Add specs for Projects::ApproversController



See merge request !327

[Elastic] Stabilize database indexer if database is inconsistent

Fixes https://gitlab.com/gitlab-org/gitlab-ee/issues/459

See merge request !328

API: Add iid filter to milestones

This was documented in the API docs but it was never working because the iid filter was never applied to the milestones. The tests were working by accident because the were checking the first element, which was by accident the request element. 

* Closes https://github.com/gitlabhq/gitlabhq/issues/10122

See merge request !3588

API: Expose updated_at for notes

* Closes #7954

See merge request !3560

API: Expose open_issues_count, closed_issues_count, open_merge_requests_count on labels

Partly fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/13238

See merge request !3569

Fix milestone removal problem when editing issues

fixes #1752 

See merge request !3571

update gitlab-elastic-search gem

Fixes https://gitlab.com/gitlab-org/gitlab-elasticsearch-git/issues/3

See merge request !330

Instrument Banzai code

See merge request !3659

Fix scroll bars shown in Revert dialogue box


## What does this MR do?

Eliminate scroll bars shown in Revert dialogue box, see the screenshots.

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

N/A

## Why was this MR needed?

Ugly scroll bars are shown in Revert dialogue box.

## What are the relevant issue numbers?

N/A

## Screenshots

![Screen_Shot_2016-04-05_at_15.27.10](/uploads/428295858ada7cd2fcdf1e831c42f8ec/Screen_Shot_2016-04-05_at_15.27.10.png)



See merge request !3532

Go back to gitlab-workhorse 0.7.1

See merge request !3656

We found out that 0.7.2 breaks shallow `git clone`. GitLab 8.7 will
work fine with gitlab-workhorse 0.7.1 too.

Fixed issue with dashboard/issues not filtering by milestone

Closes #15128

See merge request !3650

Decrease threshold for ABC Size metric in Rubocop

To 55.

References #3444

See merge request !3598

Store block timings as transaction values

See merge request !3649

If the measure method uses Transaction.current directly the SQL
subscriber (Subscribers::ActiveRecord) will add timings of queries
triggered by DB cleaner.

Standardize the way we check for and display form errors

- Some views had a "Close" button. We've removed this, because we don't
  want users accidentally hiding the validation errors and not knowing
  what needs to be fixed.
- Some views used `li`, some used `p`, some used `span`. We've
  standardized on `li`.
- Some views only showed the first error. We've standardized on showing
  all of them.
- Some views added an `#error_explanation` div, which we've made
  standard.

See merge request !3531