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Fixes #292 

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

See merge request !164

Added documentation about the use of Dpl

Please review.

1. Is that clear how to use Dpl?
2. Where the examples should be stored?
3. What should be else added? Maybe example for different provider?

See merge request !170

Added information about building projects using Docker

/cc @JobV

See merge request !178

Update annotations

I don't think that we need entry in log for this change.

/cc @vsizov

See merge request !189

Added support for image and services in YAML

- [x] Prepare changes for GitLab CI
- [x] Prepare documentation (70% done): https://gitlab.com/gitlab-org/gitlab-ci/merge_requests/178
- [x] Prepare GitLab Runner - changes are pushed to bleeding edge

/cc @vsizov

See merge request !181

Remove old sessions in order to force a new access_token access

/cc @vsizov @jacobvosmaer

See merge request !188

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

Refactoring: Get rid of private_token usage in the frontend

See merge request !185

Rounded coverage on commit page

https://dev.gitlab.org/gitlab/gitlab-ci/issues/312

See merge request !184

Change favicon

https://dev.gitlab.org/gitlab/gitlab-ci/issues/292

See merge request !183

Redirect back after authorization

https://dev.gitlab.org/gitlab/gitlab-ci/issues/287

See merge request !182

Enhance YAML validation

/cc @vsizov

See merge request !180

Update nokogiri version to remove warnings about libxml version mismatch.

GitLab [is using this version of nokogiri](https://gitlab.com/gitlab-org/gitlab-ce/blob/7-12-stable/Gemfile.lock#L378-379) too. The difference between current version and latest version is in multiple security and bug fixes as well as some features, see [their changelog](https://github.com/sparklemotion/nokogiri/blob/master/CHANGELOG.rdoc).

Reason why I've created this MR is that upgrading to 1.6.6.2 removes warnings about libxml version mismatch when running ci rake tasks in omnibus as shown here: omnibus-gitlab#636 .

See merge request !179

Build status Badge: unable to obtain code

https://dev.gitlab.org/gitlab/gitlab-ci/issues/304

See merge request !177

Improved validation of .gitlab-ci.yml

https://dev.gitlab.org/gitlab/gitlab-ci/issues/305

See merge request !176