mdns patch for vino (using avahi)

[Sebastien ESTIENNE <sebastien estienne gmail com>]

hello,

i wrote a patch to add zeroconf support to vino using avahi.
The patch publish both the vnc server and the built-in web server if enable.

As code freeze is approaching soon, it would be great if someone could 
review the patch for inclusion. (the main maintainer is busy these days)

http://bugzilla.gnome.org/show_bug.cgi?id=159874

thanx
--
Sebastien Estienne