DjangoRESTFramework: API reference categories

Looking at Django REST Framework docs, I noticed that "Ref: Authentication" category doesn't really look good and isn't what it should be: the modules reference.

I noticed that Django docs do this very well, by grouping class/method reference by their top level modules ("django.apps"). The same principle could be used in DRF, as in "rest_framework.authentication".

I'm willing to make it so (I made it ugly in the first place...)