Break device mode class driver interfaces into seperate config and state structs which are then combined, for clarity. Move device mode class driver interfaces back into the device mode class driver headers from the common class headers to make room for host class interfaces.

Enhanced class drivers to use the same public/private section seperations as other portions of the library.

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.

Changed to new device mode Class Driver function name prefixes to make way for similar host mode Class drivers.

Deleted Host ClassDriver demos -- not yet started, faster to rebase new ClassDriver demos from the newly schedulerless LowLevel host demos rather than re-convert each demo from the previous scheduler-based implementations.

Fixes to MassStorageHost demo to improve compatibility with more USB drives.

Added multiple Report ID support to the HID class driver. Removed OUT endpoint support from HID driver (all OUT reports are now processed through control requests) as a seperate endpoint had issues with determining the exact output report length.

Added Doxygen documentation to the Audio class driver. Added new modules for each of the new device class drivers to the library documentation.

Redocumented all device demos, now that they have changed over to the new USB class drivers.

Added C linkage to class drivers for C++ support.

Added prefixes to most of the class driver constants to prevent name clashes.

Removed new Start of Frame event from the library; performance suffered far too much and it was only useful in one of the standard classes (HID). Altered HID demos to use the previous method of tracking millisecond periods via a hardware timer rather than the SOF events.

Fixed MIDI class driver blocking on unread events to the host.

Commit of new class abstraction APIs for all device demos other than the MIDI demo - not documented yet.

Removed scheduler and memory allocation libraries.

Added new EVENT_USB_StartOfFrame event in the library to indicate the start of each USB frame (when generated).

Removed Tx interrupt from the USBtoSerial demo; now sends characters via polling to ensure more time for the Rx interrupt.