cleanup Gemfile
start README, include basic dev setup instructions
use sql schema format
initial empty PostgreSQL schema
install rspec-rails
install factory_girl_rails
install guard-rspec
add minitest gem to silence warning during tests

see
http://stackoverflow.com/questions/19324209/why-am-i-getting-this-minite
st-error-even-though-i-never-use-minitest for more
Mtg::Set model
foreign_key constraint migration helpers
Mtg::Card model
update "=>" syntax to ":"
import sets and cards from mtgjson.com