* Remove chording as it is not documented, not used, and needs work.
* Make Leader Key an optional feature.
* Switch from `PREVENT_STUCK_MODIFIERS` to `STRICT_LAYER_RELEASE`
* Remove `#define PREVENT_STUCK_MODIFIERS` from keymaps.
* Configurator support
* Add LAYOUTS = planck_mit to rules.mk
* Disable Tap Dance at the keyboard level
* Keymap refactor: QMK_KEYBOARD_H; enable Tap Dance for default keymap
* Add keymaps/default/rules.mk to enable Tap Dance
* Reverse the addition of config.h in keyboards/tetris/keymaps/default/