[1.8.x] Amended get_all_related_objects() backwards compatible replacement.
[1.8.x] Amended get_all_related_objects() backwards compatible replacement.

Backport of d84f01ff08922c70f9bb0861846c8ace0764b2dc from master

pquentin/django,h4r5h1t/django-hauthy,h4r5h1t/django-hauthy,h4r5h1t/django-hauthy,h4r5h1t/django-hauthy,pquentin/django,pquentin/django