add structure for many-to-one tests based on django
add broken test for reverse lookup of many-to-one relations
removed many-to-one tests, we can't support feature parity there. moved reverse related test to qdjangomodel test.
added isValid to QDjangoMetaModel
made QDjango::metaModel a little smarter for reverse lookups
added isValid for QDjangoMetaModel to determine if its default constructed or not
add extra check just for filter
add reverse lookup support to QDjangoQuerySet
use models primary key rather than forcing "id"
Merge pull request #1 from mbroadst/reverse-many-to-one-lookups

Add support for reverse lookups for many-to-one relations