Fixed #20500 - Updated flatpages URLconf example to work with APPEND_SLASH.

Thanks josh.23.french@.

docs/ref/contrib/flatpages.txt

@@ -82,9 +82,15 @@ to place the pattern at the end of the other urlpatterns::
 
     # Your other patterns here
     urlpatterns += patterns('django.contrib.flatpages.views',
-        (r'^(?P<url>.*)$', 'flatpage'),
+        (r'^(?P<url>.*/)$', 'flatpage'),
     )
 
+.. warning::
+
+    If you set :setting:`APPEND_SLASH` to ``False``, you must remove the slash
+    in the catchall pattern or flatpages without a trailing slash will not be
+    matched.
+
 Another common setup is to use flat pages for a limited set of known pages and
 to hard code the urls, so you can reference them with the :ttag:`url` template
 tag::