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* Add Django 1.5 and 1.6 support
* Add proxy model support
* Add default admin ``list_filter`` for polymorphic model type.
* Fix queryset support of related objects.
* Performed an overall cleanup of the project
* **Deprecated** the ``queryset_class`` argument of the ``PolymorphicManager`` constructor, use the class attribute instead.
* **Dropped** Django 1.1, 1.2 and 1.3 support