Backport CI service refactoring from EE

It allows easier contribution of different CI services.
Fixes #1280

Conflicts:
	CHANGELOG
	VERSION

Use newer git version

Fixes #1272

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

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

It allows easier contribution of different CI services
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Gitlab shell upgrade might be required

Also got rid of `sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production` since gitlab:check is more important.

Don't show remove branch button if you are not allowed to remove it

Fixes #1213

Move script to bin

Fixes #925

permissions for MR page
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Gitlab shell in upgrader guide

Fixes #1214

Add titles to help pages

Fixes #1183

LDAP user filter fix

Merge patch changelog back into master

/cc @dzaporozhets

This reverts commit e9d4587f, which is
incompatible with GitLab's built in LDAP user filter: a GitLab LDAP
filter is [added on top of the other filters used to find the
user](https://gitlab.com/gitlab-org/gitlab-ce/blob/982d4d51e8110bec280eb00db0fb756b062103d9/lib/gitlab/ldap/adapter.rb#L61)

Example GitLab LDAP filter: `(memberOf=cn=foo,dc=bar)`.

In contrast, an omniauth-ldap filter [replaces the 'normal'
filters](https://gitlab.com/gitlab-org/omniauth-ldap/blob/76d77543dec0c585bb4e974262f43675f9810953/lib/omniauth/strategies/ldap.rb#L55)

Example omniauth-ldap user filter:
`(&(uid=%{username})(memberOf=cn=foo,dc=bar))`.

Compare api

Fixes #1165

Review changelog

@dzaporozhets updates the changelog and notifies the team.

Improve merge request page UX

Increase Discussions and Changes tabs size. Added count of changes and comment to it

Before and after:

![Screenshot 2014-05-27 12.08.42](https://dev.gitlab.org/uploads/dzaporozhets/gitlabhq/31fe70c9be/Screenshot_2014-05-27_12.08.42.png)

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

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

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

No link inside code block

Improve rake test

Check for `system` call return value instead of `$?.exitstatus`

CSS truncation

Use css truncation for event titles on dashboard. Fix vertical align of timestamps

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

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