fixed associations and added join tables for lineitemoptions and productoptions
added show/index actions in controllers and routes for Products and Categories
added seeds
added nested routes with controller actions for products and categories
modified migrations to reflect schema we drew out on board and reset/reseeded database; changed category model to support nesting
updated routes and seeds for nested categories; updated lineitem and option and product models with the has_many through associations
Merge pull request #2 from ShaynaCummings/new_models

New models