Merge branch 'master' into 0.8

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

tests/all_warnings/__init__.py

@@ -69,7 +69,7 @@ class AllWarnings(unittest.TestCase):
         p2.parent.name = "Poppa Wilson"
         p2.save()
 
-        self.assertEqual(len(self.warning_list), 1)
+        self.assertTrue(len(self.warning_list) > 0)
         if len(self.warning_list) > 1:
             print self.warning_list
         warning = self.warning_list[0]
@@ -91,4 +91,4 @@ class AllWarnings(unittest.TestCase):
                          InheritedDocumentFailTest._get_collection_name())
 
 import sys
-sys.path[0:0] = [""]
+sys.path[0:0] = [""]