Add new ARCH option to the makefiles to (eventually) specify the target device architecture. Update non-usb peripheral drivers to reflect future multiple architecture support.

Add static keyword to all project globals whose scope should be restricted to the same module as they are declared in.

Tighten up the HID class bootloader code slightly, document that it currently exceeds 2KB of bootloader space for all models other than the Series 2 USB AVRs.

Add const to all project descriptor definitions for safety.

Add new HID_DESCRIPTOR_VENDOR() macro, change over all projects and Device ClassDriver demos to use it.

Fix reversed byte ordering of multi-byte HID data.

Added support to the HID parser for extended USAGE items that contain the usage page as well as the usage index.

Removed the HID_IOF_NON_VOLATILE and HID_IOF_VOLATILE flags from HID INPUT items where the flag is invalid. Changed over HID OUTPUT items to use HID_IOF_NON_VOLATILE.

Change over MagStripe project to use HID_DESCRIPTOR_KEYBOARD() for its HID report. Change over MouseHostDevice demo to use HID_DESCRIPTOR_MOUSE() for its HID report.

Fixed ReportID not being removed from the feature/out report data array in the HID class driver when Report IDs are used.

Added new MAX() and MIN() convenience macros.