[master] 06762cf How to call purge from recv.

[Per Buer]

commit 06762cf62ac4284b0c33a503b9d57f8b22306368
Author: Per Buer <perbu at varnish-software.com>
Date:   Thu Mar 20 11:28:28 2014 +0100

    How to call purge from recv.

diff --git a/doc/sphinx/users-guide/vcl-built-in-subs.rst b/doc/sphinx/users-guide/vcl-built-in-subs.rst
index 7a31aef..f71dfc1 100644
--- a/doc/sphinx/users-guide/vcl-built-in-subs.rst
+++ b/doc/sphinx/users-guide/vcl-built-in-subs.rst
@@ -36,8 +36,8 @@ of the following keywords:
     caching. Passes the control over to vcl_hash.
 
   purge
-    Calls vcl_purge where the object will be purged.
-
+    Purge the object and it's variants. Control passes through 
+    vcl_hash to vcl_purge.
 
 vcl_pipe
 ~~~~~~~~