DRYs up Controller 'ready' events.

 On branch base_layout_controllers
	modified:   app/assets/javascripts/backbone/lib/components/header/show/show_controller.js.coffee
	modified:   app/assets/javascripts/backbone/lib/components/layouts/base/layout_controller.js.coffee
	modified:   app/assets/javascripts/backbone/lib/components/layouts/header_sidebars/layout_controller.js.coffee
	modified:   app/assets/javascripts/backbone/lib/concerns/controllers/show.js.coffee