sync servicetest.py from Gabble
sync servicetest.py from Gabble

The only change is the path argument of dbus-signal events which is the
full D-Bus path and not the truncated one as in Gabble.

freedesktop-unofficial-mirror/telepathy__telepathy-salut,freedesktop-unofficial-mirror/telepathy__telepathy-salut,freedesktop-unofficial-mirror/telepathy__telepathy-salut,freedesktop-unofficial-mirror/telepathy__telepathy-salut