Provide better email subject lines from email on push service

If one commit is pushed, display the commit message in the subject
line. Otherwise display the number of commits pushed to the repository.
Merge pull request #6831 from pkill/better-email-on-push-subject

Provide better email subject lines from email on push service
Clean up the readme.
Merge branch 'consistent-readme' into 'master'

Consistent readme
Show/hide issue assignee avatar depends on drag-n-drop column in milestone view

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Use same size headers. Add PullReview. Mention shell guide as created by us.
Small UI fix

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Dont install production gems for travis

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

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Merge branch 'kanban-fixes' into 'master'

Kanban improvements

When drag from unassigned to assigned column - issue assignee avatar updated
Merge branch 'consistent-headers' into 'master'

Consistent headers