Integrate with Angular's CSRF support

See the top answer here: http://stackoverflow.com/questions/14734243/rails-csrf-protection-angular-js-protect-from-forgery-makes-me-to-log-out-on
Rename devise migration

I'm planning on using a single migration for the whole db until there's
actually a need for migrations.
Remove extra comments from admin table creation
Sketch db schema

This isn't meant to be at all complete.
Update schema
Remove .keep file
Stub models associated with pieces
Fill in model associations