- Remove ReturnsController, returns.js, return views, and separate return button on nav.
 - Remove swap, checkout, and x_game button.
 - Change checkout to be submitted on game_barcode field change.
 - Add optional swap checkbox when current checkouts == 1.
 - Move returns logic and actions to checkouts. Respective changes made to controller, .js, and views.
 - Change attendee ajax call to get all data regarding current checkouts and validity.
 - Remove unused methods from ApplicationController.
 - Move checkout method from Application to Checkouts controller.
 - Change attendee and game model to use non-deprecated method for primary key.
 - Add title_name and publisher_name methods to game model.
 - Fixed return link on checkouts index. (TODO: Need to modify this to be ajax and remove row on completion.)
 - Add to_bool method to String.
 - Modify attendee retrieve to leave open possibility of searching for attendee by non-id means (search by name, etc.).
 - Modify other routes as needed for above changes.