Corrected typo from r13154.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@13157 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/ref/contrib/index.txt

@@ -168,7 +168,7 @@ For more documentation, read the source code in
 ReStructured Text
 -----------------
 
-When using the `restructuredtext` markup fiilter you can define a :setting:`RESTRUCTUREDTEXT_FORMAT_SETTINGS`
+When using the `restructuredtext` markup filter you can define a :setting:`RESTRUCTUREDTEXT_FORMAT_SETTINGS`
 in your django settings to override the default writer settings. See the `restructuredtext writer settings`_ for
 details on what these settings are.