dundee: Initial GDBusClient for BlueZ 5

This patch adds the callbacks to track additions and removals of
BlueZ related interfaces and property changes in these interfaces.
bluez5: Add DUN_GW_UUID
dundee: Add mechanism to store bluetooth devices

This patch adds a hash that will store every known bluetooth
device that implements DUN service.
dundee: Add tracking of bluetooth devices

This patch tracks the GDBusProxy for Bluetooth devices in order to
be able to get their properties and register them when they
implement DUN.
dundee: Listen to devices property changes

When a bluetooth device property change and this property is Alias
or UUIDs, we need to refresh our representation of this device.
dundee: Add dundee device driver skeleton

This patch adds the functions to be called when the dundee will
connect or disconnect with a Bluetooth device.
dundee: Register/unregister dundee device

This patch adds the dundee device struct to the our Bluetooth
device representation.
dundee: Add BlueZ Profile handler

This patch declares the external dundee Profile handler. It
contains the initial implementation of the D-Bus Profile1
interface and methods responsible for handling Bluetooth
connections.
dundee: Add support for driver connect/disconnect

This patch glues together the dundee driver interface with the
D-Bus Profile1 interface.

When the dundee driver requests a connection, it will call the
Device1's ConnectProfile. And when the dundee driver requests
a disconnection, it will call Device1's DisconnectProfile.
dundee: Handle a new Profile connect from BlueZ

This patch parses the arguments in the message and returns the
file descriptor to dundee device implementation.
dundee: Handle a Profile disconnection from BlueZ

This patches shutdowns the file descriptor and returns to dundee
device implementation.