Fixed #17132 -- remove a leftover reference to django.conf.default.urls in...

Fixed #17132 -- remove a leftover reference to django.conf.default.urls in Django.  THanks to claudep for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17048 bcc190cf-cafb-0310-a4f2-bffc1f526a37