Add information on support for creating subclasses in the model

[anonymous]

I'm new to Django, and it seems like support for defining subclasses in the model (e.g. defining a "Person" model class, and then "Employee" that extends Person) is in flux--perhaps it was supported to some extent in past revisions, but is being changed? At any rate, for people coming to Django from other frameworks it'd be helpful if in your FAQ you could address the issue.

[Jacob]

I think it's not worth writing about until we have something better than "it doesn't work right" to say.