Added git gc for housekeeping
This merge request will add the gc functionality used by the housekeeping function in the project settings page.
see gitlab-org/gitlab-ce#3041 and https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/1658
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
This merge request will add the gc functionality used by the housekeeping function in the project settings page.
see gitlab-org/gitlab-ce#3041 and https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/1658