Allow filtering issues that have no milestone or assignee

Correct usage of "Can't"

Fix current class for hooks tab in admin section

Signed-off-by: Martin Bastien <martin.bastien@studiofrenetic.com>

GFM Refactoring

Makes use of 'extended' patterns to add comments to the groups, and also
reduces the total number of groups to just those that are used.

Continues #1222

Closes #1222

Fix invalid syntax in OmniAuth initializer sample

Merge branch 'fix_commits_dashboard' of https://github.com/jouve/gitlabhq into jouve-fix_commits_dashboard

Conflicts:
	app/views/events/_commit.html.haml

Updated MySQL docs and Ubuntu auto-install script

Fully embrace Ruby 1.9 hash syntax

Features are still expecting the 1.8 syntax, which is fine in this case.