[3.0] cbd6a3f Fix typo

[Tollef Fog Heen]

commit cbd6a3fa55e0919db34657a2447f798500c17e55
Author: Tollef Fog Heen <tfheen at varnish-software.com>
Date:   Wed Aug 10 11:26:04 2011 +0200

    Fix typo

diff --git a/doc/sphinx/installation/upgrade.rst b/doc/sphinx/installation/upgrade.rst
index d0e8ade..5cb5ad7 100644
--- a/doc/sphinx/installation/upgrade.rst
+++ b/doc/sphinx/installation/upgrade.rst
@@ -57,7 +57,7 @@ becomes
 ``beresp.cacheable`` is gone
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-``beresp.cacheable`` is gone, and can be replaced with ``beresp.ttl > 0``
+``beresp.cacheable`` is gone, and can be replaced with ``beresp.ttl > 0s``
 
 returns are now done with the ``return()`` function
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~