Improve white code highlight in comments and wiki

![Screenshot 2014-11-05 16.36.55](https://dev.gitlab.org/uploads/dzaporozhets/gitlabhq/5723848593/Screenshot_2014-11-05_16.36.55.png)

See merge request !1241

Do not mention MR if commit is a part of MR

See merge request !1242

Fix system_silent call

Origin request has been provided by our contributor @cirosantilli. We had to revert it and rework.

origin commit - https://dev.gitlab.org/gitlab/gitlabhq/commit/0b1084a4538bc46684c8620410988d3b1093e7ab

See merge request !1243

This reverts commit b33d4bc2.

This reverts commit 0b1084a4.

Factor using Repository#path_to_repo

Update GitLab CI service to work with new GitLab CI

See merge request !1239

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

Remove unnecessary authorisations

Because we already check read_project ability in `before_filter :project`

See merge request !1240

Remove unused authenticate_user from project#show

Remove dead Event#new_branch? method

Don't output to stdout from lib non-interactive methods [failure unrelated]

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

Factor '0' * 40 blank ref constants [failure unrelated]

Fix version of test seed branches to specific revisions. Only clone if necessary.

Transform remove blob link into button.

improve SSH key emails

Fix log rotate permission error

It pollutes the test output too much.

Use xmlschema date format (ISO 8601) on system hooks timestamp

Attachment URL with non-/ relative root

Update default regex message to match regex.

Add issueable actor to hooks

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

Continue strings with backslash instead of append

Factor behaviors.scss constants

clarify that 'template1=#' is part of prompt

Quit the database session at end of database setup

Expose projects_limit through users API if UserFull.