avahi: change initscript to start on boot
dbus: change initscript to start on boot, add STARTLEVEL=90 to start it before avahi is started
sane-backends: add option to enable avahi support, add standalone mode


git-svn-id: file:///var/svn/freetz/trunk@9804 149334a1-2f27-0410-a3b9-fc62619ac1e6