Added new reciever to start OpenXC services when Bluetooth VI is connected.
Added PreferenceManager start to Bootup reciever so that Bluetooth will connect after boot before enabler is opened.
Merge branch 'next' into pr/95
Grab log TAG without a hard coded string.
Let PreferenceManagerService start VehicleManager on bootup.

There's no explicit need to start VehicleManager on bootup, the actual
requirement is the VehicleService (so there's an instance running for
remote processes to use) and the PreferenceManagerService, so the data
sources are re-connected.
Store VI Bluetooth device name prefix in a central place.