Document timescale of srcaddr->ttl

git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@1672 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache_session.c

@@ -91,6 +91,7 @@ struct srcaddr {
 	char			addr[TCP_ADDRBUFSIZE];
 	unsigned		nref;
 
+	/* How long to keep entry around.  Inherits timescale from t_open */
 	double			ttl;
 
 	struct acct		acct;