* 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
* Add initial event manager implementation,
roughly mimicking Nordic's API.
* Add `position_state_changed` and
`keycode_state_changed` events.
* Hook up HID and keymap to new events
instead of using behaviour global event
crazy.
* Move all headers to `include/zmk` directory.
* Update includes to reference them properly.
* Add `keymap.c` file from keymap, if found.
* Toplevel CONFIG_ZMK_BLE aggregate config setting.