Missing merge bits.
Tree cleanup.
Fix GroupController.
Fix STATUS_* in MessageController.
GroupUser: Add getGroups and getUsers.

Maybe add a filter functionality in RModel later.
Fix SELECT issue when JOIN is used.
Fix most old parts of PostController.
Merge branch 'ActiveRecord' into Raysmond

Conflicts:
	app/controllers/GroupController.php
	app/controllers/PostController.php
	app/models/GroupUser.php
	app/models/User.php
	rays/base/RModel.php