Track compatible gitlab-git-http-server version

The 'git archive' changes in GitLab 8.1 require a version of
gitlab-git-http-server that is incompatible with GitLab 8.0, so we
need to keep track of this now.

See merge request !1603

Improve typography



See merge request !1622

Dont put padding on typography but on holder elements instead
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Fixes wrong padding of wiki content. 


cc @JobV @skyruler 

See merge request !1620

Make selectbox options more compact
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

See merge request !1619

Highlight comment based on anchor in URL
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Fix for #2954 

See merge request !1618

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>

Add index on ci_commits.gl_project_id



See merge request !1616

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

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

Fixes #3086

Show last commit from default branch on project home page

Implements #2705 

Screenshot: 

![Screenshot_2015-10-15_19.03.29](https://gitlab.com/gitlab-org/gitlab-ce/uploads/ef1cfa6764ab0ec5e7584ae61980a47d/Screenshot_2015-10-15_19.03.29.png)
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

cc @skyruler 

See merge request !1610

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

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

Add a system note and update relevant merge requests when a branch is deleted or re-added

If a branch is deleted with an open merge request, amended offline, and then pushed again,
GitLab doesn't bother to update the merge request even though the last commit ID and/or
code may have changed. This MR ensures that each push will update any relevant merge
requests and adds a system note if this happens as well.

The new messages look like:

![image](https://gitlab.com/gitlab-org/gitlab-ce/uploads/6581eea069cd8e485b7fa4187ed4c043/image.png)

Closes #2926 

See merge request !1601

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

If a branch is deleted with an open merge request, amended offline, and then pushed again,
GitLab doesn't bother to update the merge request even though the last commit ID and/or
code may have changed. This MR ensures that each push will update any relevant merge
requests and adds a system note if this happens as well.

Closes #2926

Changed loose to lose

Implement when syntax in .gitlab-ci.yml

See merge request !1606

[ci skip]

Also adds a preamble note that a working 8.0 installation (i.e.,
gitlab-git-http-server, updated Nginx/Apache configs) is required before
proceeding.

[ci skip]

[ci skip]

Sentences end in periods.

[ci skip]

See merge request !1604

Prepare 8.1 documentation

[ci skip]

See merge request !1612

Update redcarpet gem. Fixes gem memory leak

Fixes #2773 

See merge request !1607