Fixed #13287 -- Corrected the advice on argument formatting in the {% url %}...

Fixed #13287 -- Corrected the advice on argument formatting in the {% url %} tag. Thanks to Gabriel Hurley for the report.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@13107 bcc190cf-cafb-0310-a4f2-bffc1f526a37