Fix RESTfulness of project hook deletions by API

API: creating last project before limit returns 404

API: fixes visibility of project hook

Add commit full time tooltip to `commited_ago`

Update doc/install/installation.md

Update seeds for state columns

changed installation overview list step #4
Gitolite -> GitLab shell 

Event already has author relation

Fix development fixture for gitlab_shell

Conflicts:
	app/models/issue.rb
	app/models/merge_request.rb

Sort groups alphabetically on dashboard page