Adds files per commit, created/deleted/compare to hook data.

Switches gitlab_git to forked version; uses quick_diffs to get hook files.
Adds Gemfile ref to gitlab_grit forked version (used by gitlab_git).
Increased web hook timeout from 10s to 60s.
Adds case-insensitive sort to tree views.
Adds tags list (which tags contain commit) on commit page.