[1.1.X] Fixed #12524 -- Clarified handling of pre-1000AD dates in datetime_safe (and thus, the serializers). Patch includes moving the datetime_safe tests into the utils regressiontests module. Thanks to gsf for the report and initial patch.

Backport of r12423 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@12424 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/regressiontests/utils/tests.py

@@ -10,6 +10,7 @@ from django.utils.functional import SimpleLazyObject
 import timesince
 import datastructures
 import dateformat
+import datetime_safe
 import itercompat
 from decorators import DecoratorFromMiddlewareTests
 from functional import FunctionalTestCase
@@ -25,6 +26,7 @@ except NameError:
 __test__ = {
     'timesince': timesince,
     'datastructures': datastructures,
+    'datetime_safe': datetime_safe,
     'itercompat': itercompat,
 }