Start application process

Moved enrollments controller to users controller and will use enrollments for new applications. Renamed a bunch of stuff involving enrollments to be "user" as needed. Setup base form for enrollments with prototype of autocomplete per Ehud. Cleaned up related javascripts and consolidated. Added enrollment model and associations.
I love comments like these.  It saves so much time over the life of the code for new people not to have to figure out what the heck the code is there for or changing back to the old broken way to try and fix a future bug only to reintroduce the behavior you describe.