avahi: be quiet on startup

Signed-off-by: Stephan Raue <stephan@linux-2.fritz.box>
Merge branch 'openelec-3.0' of github.com:OpenELEC/OpenELEC.tv into openelec-3.0
dbus: add wait_for_dbus() & respawn
connman: depends on dbus, so wait for it
ConsoleKit: depends on dbus, so wait for it & respawn
udisks: depends on dbus, so wait for it

TODO: respawn ?
xbmc: depends on dbus, so wait for it
avahi: depends on dbus, so wait for it

Signed-off-by: Stephan Raue <stephan@openelec.tv>