dundee: Fix typo in Manager's signal DeviceAdded

This typo was preventing dundee from sending the signal.
dundee: Fix typo in dundee-disconnect test
AUTHORS: Mention Paulo's contributions
gdbus: Always unreference the message in g_dbus_send_message()

A quick fix on g_dbus_send_message(), if check_signal() fails it returns
FALSE without unreferencing the message as it should. This patch fixes
it.
handsfree-audio: Initial DBUS code

This code can register an handsfree audio agent and receive NewConnection and
Release calls.
handsfree-audio: Build handsfree-audio command line tool