Renamed the Serial byte send/receive functions to remain consistent with the CDC driver's byte functions.
Altered the serial byte receive function to make it non-blocking.
Altered all low level device and host mode demos to ensure that endpoints and pipes are configured in ascending order properly.
Rewrote all low level host mode demos' configuration descriptor parser code to ensure that pipes are enumerated in ascending order, and to ensure maximum compatibility with devices.
Incremented all device mode demo's device descriptor revision numbers to ensure that any descriptor changes are re-fetched on machines which have enumerated previous versions.
Added brace guards to macros with parameters to prevent unintended changed evaluation of the macro expression.
Minor code cleanups (remove redundant comments, fix spacing, etc.).
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.