Remove VBUS events - not needed as the library takes care of VBUS detection and feedback on supported AVRs via the USB_Device_Connected and USB_Device_Disconnected events.
Fixed incorrect Host state assignment in the incomplete BluetoothHost demo.
Make all audio device Class Driver functions require a reference to the Audio class instance, so that the endpoint size can be checked (and to standardize the APIs).
Make LEDs more responsive in the AudioOutput device demos.
Split out common defines/types from class drivers into a seperate common class driver directory.
Make central USB Class driver dispatch headers, used for both device and host modes.