Add the ErrorDocument for 502 and fix 503 for GitLab 8.8 release
Brings the Apache site configurations up-to-date with the latest error document pages in GitLab 8.8
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Brings the Apache site configurations up-to-date with the latest error document pages in GitLab 8.8