[1.8.x] Fixed #24052 -- Doc'd how to write data migrations with models in multiple apps.
[1.8.x] Fixed #24052 -- Doc'd how to write data migrations with models in multiple apps.

Backport of b089759d6025582f36fbea3c4be3855c50b82462 from master

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