Voter type being incorrectly set for extended classes on up / down vote

[jeffreyiacono]

Let say we have User that inherits from ActiveRecord::Base and Admin that inherits from User. The User is a voter (make_voter). Creating an up / down vote for an instance of User works great. However, an up / down vote for an instance of Admin will incorrectly set the voter_type to "User". To compound issues, #up_voted? / #down_voted? check against a voter_type of "Admin" for Admin instances, so a voteable item that has been voted on will incorrectly report that you have not yet voted on the item in question. With this check failing, you could incorrectly display voting controls in your UI, which will raise an AlreadyVotedError if implemented against #up_vote / #down_vote.

Failing test: jeffreyiacono@2d4aa11