* Fire an event w/ layer number, state, and timestamp
when a layer is activated/deactivated.
* Add `zmk_keymap_highest_layer_active()` query.
Co-authored-by: KemoNine <mcrosson@kemonine.info>
* Add timestamps to position events and behaviors.
- Take original event timestamps into consideration so nested tap-holds have proper timing.
- Add position and timestamp to keycode state changed event so the one-shot behavior can properly identify other keypresses and timings.
- Add timestamp to position events received from peripheral
* reduce number of arguments to behaviors
* Use extra comptible = "zmk,behavior-global" to add
behaviors to global bindings for event notification.
* Implement mod-tap, as a keymap binding and global one
to skip tap if other keycode pressed while held.
