Fixed #13120: Corrected typo in middleware doc. Thanks django@willhardy.com.au.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12793 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/topics/http/middleware.txt

@@ -31,7 +31,7 @@ created by :djadmin:`django-admin.py startproject <startproject>`::
         'django.contrib.sessions.middleware.SessionMiddleware',
         'django.middleware.csrf.CsrfViewMiddleware',
         'django.contrib.auth.middleware.AuthenticationMiddleware',
-        'django.contrib.messages.middleware.MessageMiddleware,
+        'django.contrib.messages.middleware.MessageMiddleware',
     )
 
 During the request phases (:meth:`process_request` and :meth:`process_view`