MR push comment "N commits from branch master" doesn't always link to the intended comparison page
See the note here: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/326#note_984907
2aaf6853..dbd347bf links to https://gitlab.com/gitlab-org/gitlab-ce/compare/2aaf6853%5E...dbd347bf which only shows 4 commits, instead of all 39 at https://gitlab.com/haynes/gitlab-ce/compare/96e9d0855a0265bc6023eaa52703a2765f53ffcd...dbd347bf.
I wrote the functionality and have an idea of where the issue lies, so I'll look into it today.
