Simplify controllers and layout handling
Created by: jouve
Controllers related to projects (Projects, Commits, Hooks, ...) share common code (layout :project, before_filters :project and :add_project_abilites), so I created a ProjectController < ApplicationController to put this common code and made all ProjectsController, CommitsController, HooksController, ... inherit this ProjectController.
Second commit removes most of layout calls to use default rails layout logic (layout with same name as controller).