Custom User Model

So there was a problem with the actual migrations in the repository. Whenever migrations where ran it didn't care what is in settings for AUTH_USER_MODEL it would set the ForeignKey on FacebookCustomUser inside OpenGraphShare.
I made FacebookCustomUser be created only if AUTH_USER_MODEL == 'django_facebook.FacebookCustomUser' so people can specify there own custom User models. Basically if anyone uses anything but FacebookCustomUser, they will have to run the schemaupdate.