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/cache/liberal_backend.py

@@ -1,5 +1,6 @@
 from django.core.cache.backends.locmem import LocMemCache
 
+
 class LiberalKeyValidationMixin(object):
     def validate_key(self, key):
         pass