Railsize forms, implement NPTT button

The front page is now a Rails-generated HTML form, using the collection_select form-helper
Changed the parameter format on the video page, to play nice with Rails. Uses the collection_select_checkboxes form-helper.
Uses Coffeescript to add highlights to the video page on-load.
I'm not clear on how safe "params.slice" is, which is used in video_controller.rb