fd24863db5
- Remove diamond inheritance tests since these test a bug in Django, not in django_polymorphic. - Fix spurious print message in test_primary_key_custom_field_problem(), where uuid instances are for some reason being compared to uuid.UUID classes. Replaced with a test that checks that the primary key values are valid UUIDs. - Remove Django > 1.6 conditionals wrapping the multiple inheritance tests and model definitions, in favor of using the definitions for Django 1.7. Django 1.7 requires a custom primary key when using concrete model inheritance because failing to do so is potentially ambiguous. Adding the custom primary key does not break tests in older Django versions.