Wasn't loading new DB records from Yelp API call

- fixed this issue by simplifying the data coming back from the API call

removed sorting method and using CDQ's sort method instead
Moved filter and get_first_category methods out of YelpAPI helper and into the Business model as private methods

Created prepare method in Business model to parse the YelpAPI repsonse
Merge pull request #15 from mjafshar/refactoring

Refactoring