v1.0

This release uses a naive macro system:

If scroll lock (LED) is enabled, F9/F10 become F11/F12; and
If num lock (LED) is disabled, numpad commands become nav commands (e.g. num7 -> home), and num5 becomes downarrow.

On XT layouts, num asterisk always outputs printscreen, even if the keyboard emits "extended" scancodes and has a dedicated prtsc key.

USB boot descriptors are untested, and platforms that consume such descriptors but don't report it will not work properly.