Fixed #17110 -- Mentionned that the {% filter %} tag doesn't support the...

Fixed #17110 -- Mentionned that the {% filter %} tag doesn't support the 'safe' and 'escape' filters. Thanks benspaulding.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@17271 bcc190cf-cafb-0310-a4f2-bffc1f526a37