Remove the lowest memory requirement of 512MB.
Create emails helper for actions links.
Include the helper for mailer, add links to emails.
Add documentation about buttons in gmail.
Set action on issue/mr creation mail.
Correctly restore empty repositories.

If a project is being restored, but there is no bundle file, the project was
empty when it was backed up.  In this case, just use git init --base to create a
new bare repository.
Update CHANGELOG for 7.5

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Add branch controller test.
Sanitize branch name and ref name
Clean the string with commit author and email.
Gitlab.com uses special packages, build them first
Update gitlab_git to 7.0.0.rc11
check browser version, blacklisting ie6 end ie7