Fixed #17652 -- Removed all mentions to Windmill from the docs as that project...

Fixed #17652 -- Removed all mentions to Windmill from the docs as that project doesn't integrate well with Django at this time.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17524 bcc190cf-cafb-0310-a4f2-bffc1f526a37