Fixed #5449 -- Noted in docs/model-api.txt that the admin date selection...

Fixed #5449 -- Noted in docs/model-api.txt that the admin date selection always starts on a Sunday. Thanks, flother

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6304 bcc190cf-cafb-0310-a4f2-bffc1f526a37