[1.2.X] Fixed #15129 -- Fixed stability of data input/output L10N format...

[1.2.X] Fixed #15129 -- Fixed stability of data input/output L10N format modules priority order. Thanks tonnzor for the report and fix.

Backport of [15402] from trunk

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@15403 bcc190cf-cafb-0310-a4f2-bffc1f526a37