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* raised minimum Django version to 1.4.x
* added Python 3.2 and Python 3.3 support
* added Django 1.5 support and initial 1.6 compatability
* FEATURE: recognition of custom model field subclasses
* FEATURE: allow optional display names for order_by values
* FEATURE: addition of class-based FilterView
* FEATURE: addition of count() method on FilterSet to prevent pagination
from loading entire queryset
* FIXED: attempts to filter on reverse side of m2m, o2o or fk would
raise an error