Add support for multidb with Django (Closes #171).

The ``factory.django.DjangoModelFactory`` now takes an extra option:

```
class MyFactory(factory.django.DjangoModelFactory):
    class Meta:
        model = models.MyModel
        database = 'replica'
```

This will create all instances of ``models.Model`` in the ``'replica'``
database.

1 files changed, 6 insertions, 0 deletions

diff --git a/tests/test_using.py b/tests/test_using.py
index 7318f2e..1d7977f 100644
--- a/tests/test_using.py
+++ b/tests/test_using.py
@@ -69,6 +69,9 @@ class FakeModel(object):
         def order_by(self, *args, **kwargs):
             return [1]
 
+        def using(self, db):
+            return self
+
     objects = FakeModelManager()
 
     def __init__(self, **kwargs):
@@ -1490,6 +1493,9 @@ class BetterFakeModelManager(object):
         instance.id = 2
         return instance, True
 
+    def using(self, db):
+        return self
+
 
 class BetterFakeModel(object):
     @classmethod