Refactor Playlist Form and Creation into PlaylistController

* Will become a sort of Resource Controller, with additional methods
  to reorder the items in a playlist.
Refactor displaying, favoriting, and Downloading Media.

* Rewrote Routes to be a little more sensible
* Use application layout
* Broke down displaying media, adding to playlists,and adding comments
  into partials
* View interaction is now recorded in controller.