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

Fixes to the MIDI device demos (ClassDriver, LowLevel); discard unused read-in events from the host, use standard MIDI event structure in low level demo rather than sending individual bytes.

Copy and convert incomplete Bluetooth Host demo to the library.

Remove outdated AVRStudio project files from demos, projects, bootloaders. Fix makefiles of ClassDriver device demos.

Move new Class Driver powered demos to a new ClassDriver subdirectory, re-add old low level demos to a LowLevel subdirectory.