[3.0] 01a2a5c req.url, not req.http.url

[Martin Blix Grydeland]

commit 01a2a5c4dfc2fb95ac516f49f0b43ded80a6c374
Author: Tollef Fog Heen <tfheen at err.no>
Date:   Wed May 30 11:17:17 2012 +0200

    req.url, not req.http.url

diff --git a/doc/sphinx/tutorial/purging.rst b/doc/sphinx/tutorial/purging.rst
index 22056a7..422f9f4 100644
--- a/doc/sphinx/tutorial/purging.rst
+++ b/doc/sphinx/tutorial/purging.rst
@@ -88,7 +88,7 @@ Support for bans is built into Varnish and available in the CLI
 interface. To ban every png object belonging on example.com, issue
 the following command::
 
-  ban req.http.host == "example.com" && req.http.url ~ "\.png$"
+  ban req.http.host == "example.com" && req.url ~ "\.png$"
 
 Quite powerful, really.