Extend ReadOnlyModelViewSet with prefetch mixins
Extend ReadOnlyModelViewSet with prefetch mixins

This change creates a ReadOnlyModelViewSet with the required prefetch mixins.
django-json-api/django-rest-framework-json-api,leo-naeka/django-rest-framework-json-api,django-json-api/rest_framework_ember,django-json-api/django-rest-framework-json-api