Convert much of the regression tests to use absolute imports. There's still work to be done though.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16976 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/regressiontests/backends/models.py

@@ -1,7 +1,6 @@
 from django.contrib.contenttypes import generic
 from django.contrib.contenttypes.models import ContentType
-from django.db import models
-from django.db import connection
+from django.db import models, connection
 
 
 class Square(models.Model):