Merge branch 'master' into 0.8

Conflicts:
	.travis.yml
	AUTHORS
	docs/changelog.rst
	mongoengine/base.py
	mongoengine/queryset.py
	tests/queryset/queryset.py

tests/queryset/queryset.py

@@ -241,7 +241,7 @@ class QuerySetTest(unittest.TestCase):
 
     def test_none(self):
         class A(Document):
-            pass
+            s = StringField()
 
         A.drop_collection()
         A().save()
@@ -249,6 +249,31 @@ class QuerySetTest(unittest.TestCase):
         self.assertEqual(list(A.objects.none()), [])
         self.assertEqual(list(A.objects.none().all()), [])
 
+        class B(Document):
+            ref = ReferenceField(A)
+            boolfield = BooleanField(default=False)
+
+        A.drop_collection()
+        B.drop_collection()
+
+        a1 = A(s="test1").save()
+        a2 = A(s="test2").save()
+
+        B(ref=a1, boolfield=True).save()
+
+        # Works
+        q1 = B.objects.filter(ref__in=[a1, a2], ref=a1)._query
+
+        # Doesn't work
+        q2 = B.objects.filter(ref__in=[a1, a2])
+        q2 = q2.filter(ref=a1)._query
+        self.assertEqual(q1, q2)
+
+        a_objects = A.objects(s='test1')
+        query = B.objects(ref__in=a_objects)
+        query = query.filter(boolfield=True)
+        self.assertEquals(query.count(), 1)
+
     def test_update_write_options(self):
         """Test that passing write_options works"""