Implement factory girl

Pivotal Tracker story Switch to FactoryGirl: https://www.pivotaltracker.com/story/show/75757844.
- add factory_girl_rails gem
- create factories for partners, provinces, sponsor_types, sponsors, statuses
- create model spec for sponsor_type using sponsor_types factory

All factories confirmed to create valid objects.
could you not use `subject.name = ''`? alternatively you could use a let block for an attribute hash: `attribute[:name] = ''`. But if this is the style you guys will be going for, I don't have an issue with it, just making sure this was intentional :wink: