Fixed #16729 -- Fixed a small typo in the settings reference doc. Thanks to...

Fixed #16729 -- Fixed a small typo in the settings reference doc. Thanks to simon.cruanes.2007@m4x.org for the report and to Aymeric Augustin for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16716 bcc190cf-cafb-0310-a4f2-bffc1f526a37