Fix up demo documentation device compatibility list to be as general as possible to reduce changes required as Atmel releases more devices within the same USB AVR series.
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.
Added new Endpoint_ClearStatusStage() convenience function to assist with the status stages of control transfers.
Removed vague USB_IsConnected global - test USB_DeviceState or USB_HostState explicitly to gain previous functionality.
Removed USB_IsSuspended global - test USB_DeviceState against DEVICE_STATE_Suspended instead.
Fixed possible enumeration errors from spinloops which may fail to exit if the USB connection is severed before the exit condition becomes true.