Add obj.hits to the vcl(7) manual

git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@4207 d4fa192b-c00b-0410-8231-f00ffab90ce4

man/vcl.7so

@@ -541,6 +541,9 @@ The object's remaining time to live, in seconds.
 .It Va obj.lastuse
 The approximate time elapsed since the object was last requests, in
 seconds.
+.It Va obj.hits
+The approximate number of times the object has been delivered. A value of 0
+indicates a cache miss.
 .El
 .Pp
 The following variables are available while determining the hash key