[TASK] Refactoring Gitlab recipes and templates

Updated the README to reflect the focus of the cookbook.
Updated the licenses.
The recipes now work with gitlab 5.1-stable.
Removed the Capistrano dependency.

Recipe users cleaned up and now focusses on git user and not also on gitlab.
Recipe gitlab refactored to support the installation requirements:
https://github.com/gitlabhq/gitlabhq/blob/master/doc/install/installation.md