IANA has reserved the 198.18.0.0/24 network for Network Interconnect Device
Benchmark Testing which vaguely fits what we are doing.  Use that
instead of 127.0.0.2 since the latter works fine to bind to on Linux
(at least).


git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@3116 d4fa192b-c00b-0410-8231-f00ffab90ce4