Fixes #3641
* 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.
* Create z.txt * Add files via upload * Delete config.h * Delete keymap.c * Delete rules.mk * Delete z.txt * Create x.txt * Add files via upload * Delete x.txt * fixing suggested issues