created users table (hopefully for real this time)
created songs table
renamed a couple files to better conform with convention; created follows table
created play counts table
updated validations
removed redundant user_id column from play_counts table before ActiveRecord blew up
updated follows table to reflect updated validations
actually performed the action described in the previous commit, but which I forgot to run rake migrate for
Created basic controllers and welcome/index view, added routes for user and songs