Expanded message handling and some diagnostic API.
Rename MeasurementListener to reflect new Message type.
Merge branch 'pr/131' into refactored-datastructures

Conflicts:
	openxc/src/com/openxc/VehicleManager.java
	openxc/src/com/openxc/sinks/AbstractQueuedCallbackSink.java
	openxc/src/com/openxc/sinks/MessageListenerSink.java
Merge in DiagnosticResponse listener notification.