Fix Django 1.7 migration for django-polymorphic 0.7
Fix Django 1.7 migration for django-polymorphic 0.7

django-fluent/django-fluent-contents,django-fluent/django-fluent-contents,edoburu/django-fluent-contents,edoburu/django-fluent-contents,ixc/django-fluent-contents,django-fluent/django-fluent-contents,ixc/django-fluent-contents,edoburu/django-fluent-contents,jpotterm/django-fluent-contents,jpotterm/django-fluent-contents,ixc/django-fluent-contents,jpotterm/django-fluent-contents