Add Bluetooth connection request/complete/disconnection callbacks.

Remove debugging from HCI layer, as it is now operational -- add guards to ACL debug statements to reduce logging chattyness so that the overall command sequences can be observed and debugged.

Add user callback function to the Bluetooth host demo to filter out connections from remote devices. Add in ability to reject connections based on their bluetooth device address.

Clean up RelayBoard project code.

Make AVRISP project clear the XMEGA target's reset register twice; this does not appear to take affect properly the first time under some circumstances.

Remove unused macro in the host mode demos for the maximum Configuration Descriptor size.

Massive cleanups to the incomplete BluetoothHost demo, to make the HCL layer code much easier to read, block less and work correctly.

Renamed all library events to properly seperate out Device and Host mode events. Changed the firing conditions for some events to ensure that events are fired by their own USB mode only.

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.

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.

Seperated out Lib components of the incomplete BluetoothHost demo application out into a seperate Lib subfolder.

Changed F_CLOCK entries in project makefiles to alias to F_CPU by default, as this is the most common case.

Pipe_ConfigurePipe() now automatically defaults IN pipes to accepting infinite IN requests, this can still be changed by calling the existing \ref Pipe_SetFiniteINRequests() function.

Copy and convert incomplete Bluetooth Host demo to the library.