Renamed beer_style as beer_genre globally in rails

- Namespace freed to use beer_style for the broader BreweryDB
- All users will need to drop and reset their database
- No issues in the process; tests still passing
Renamed beer_search_term as beer_style globally in Rails

 - We did this because beer_styles are more specific than genres
 - This is also good because it's consistent with the BreweryDB
 - There were no issues in the migration; all tests revised and pass
Merge pull request #22 from fence-lizards-2014/rename_beer_style_across_rails

Rename beer style across rails