[1.1.X] Fixed #13348: Restored ability to load models from apps in eggs....

[1.1.X] Fixed #13348: Restored ability to load models from apps in eggs. Thanks Ramiro and metzen for pointers on how to find out if a module loaded from an egg has a particular submodule.

r12982 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@12983 bcc190cf-cafb-0310-a4f2-bffc1f526a37