WIP: fixing/revising models & migrations
revised migrations to include rosters, modified attendances
revised models and migrations; added new enrollment model, removed roster, updated associations
added start_date, end_date fields to sections
added forgotten sections model
added attr_accessible in models student, enrollment, section
deleted coursework, roster, cleared seeds
Merge pull request #3 from zrivest/revise_model_migrations

Revise model migrations