Add Playlists and edit devise views

* Update devise views to have custom layouts
* Create Playlists for users
* Set authentication only users can create a playlist
* Set up users model to has_many :playlists
* Set up playlists model to belong_to :user
* Style layout including playlists, devise, and rest of site
Merge pull request #2 from jeffAwesome/add_playlists

Add Playlists and edit devise views