Fixed #13760 -- Cleaned up unnecessary default option handling in a bunch of...

Fixed #13760 -- Cleaned up unnecessary default option handling in a bunch of management commands. Thanks to Paul McMillan for the report and to adamv and Claude Paroz for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17028 bcc190cf-cafb-0310-a4f2-bffc1f526a37