Pull request for Chris Jeon (chris0374@gmail.com)

1. Clone repo
2. rake db:create db:migrate db:seed (seed if you wish, not necessary)

If there are any questions or comments, please reach out to chris0374@gmail.com.

Note:
Purchaser was not implemented as STI, because well, I don't see Purchasers from acquired companies as Users since they probably don't have a LivingSocial account (also email and passwords are not provided in the tab file)