[3.0] 2efdcc3 Fixing a typo in the documentation.

[Tollef Fog Heen]

commit 2efdcc3884c822c6640372c5d7fafed8d6d1b85d
Author: Derek Hammer <derek.r.hammer at gmail.com>
Date:   Thu Mar 8 03:11:26 2012 -0500

    Fixing a typo in the documentation.

diff --git a/doc/sphinx/tutorial/purging.rst b/doc/sphinx/tutorial/purging.rst
index 5e5768e..22056a7 100644
--- a/doc/sphinx/tutorial/purging.rst
+++ b/doc/sphinx/tutorial/purging.rst
@@ -4,7 +4,7 @@
  Purging and banning
 =====================
 
-One of the most effective way of increasing your hit ratio is to
+One of the most effective ways of increasing your hit ratio is to
 increase the time-to-live (ttl) of your objects. But, as you're aware
 of, in this twitterific day of age serving content that is outdated is
 bad for business.