Issue #15 Added basic ModelForm for track editing, updated dropdown menu in ui so that it shows the form in a modal.
JS formatting cleanup with emacs javascript-mode properly enabled
Issue #15 Added artist attribute to track
issue #15 A ton of changes for editing tracks.  More than should have been in one commit.
Created UserOwnedModelResource for api, a bunch of javascript for checking if resources exist
and modifying them for artist, album, and album artist for a track.
issue #15 Track updates are closer to working.  Can update the title, artist, and album title properly now.
issue #15 Made artist foreign key on Album model nullable.  Now editing track data which changes the artist to one
that doesn't already exist works.
issue #15 fixed some basic html issues in templates when there are multiple albums.
issue #15 Added checks for null objects whose properties are referenced in the javascript
Minor changes to allow updating resources.  Beginning of new TrackAlbumResource for denormalized updating of track and album data for a track in one request
Added new TrackAlbumResource which allows PATCH requests with track title, track artist, album title, and album artist, and properly updates the track data to match, creating any needed objects along the way
track artist, title, album artist, and album title can now all be updated from a single form.  This will create new artists or albums as needed.
Added beginnings of test cases for new TrackAlbumResource