Create the PostgreSQL database. Follow the manual instrcutions in resources/set_up_postgresql before running rake db:create
ActiveRecord migrations to create the tables
created the AR models
changed Slide.type to Slide.slide_type because type is a reserved keyword. fixed the AR models
changed PostgreSQL setup
better PostgreSQL setup instruction
additional notes on database
added presence checks to models
seeding data
Merge branch 'ting_branch_2'