Don't panic on darwin if launchctl has no output
Don't panic on darwin if launchctl has no output

Fixes #31.

guelfey/go.dbus,jonboulle/dbus,kyrofa/dbus,godbus/dbus,tpltnt/dbus,titanous/dbus,aulanov/go.dbus,dudymas/dbus,tianon/debian-golang-dbus