adds twitter bootstrap
adds basic application layout
adds user menu and links to sign in/up
style the sign-up form
style sign in form
add space to page title
styles playlist index
styles individual playlist page
configure paperclip to store files to Amazon S3
configure pretty urls for playlists
adds notices and alerts to layout
remove redundant username presence validation
songs within playists are drag-and-drop sortable
configure app for heroku and add rake task to set s3 configuration