* keeb68.h: use QMK 3-character notation
* physically arrange layout macro
Moves the keycodes for Equals and Right Bracket to their proper places on the Number and Tab rows, respectively.
Also refactors the keymaps to use QMK-native keycode aliases, grid alignment, and four-space indent.
* move `keymaps/grv_esc/readme.md` to `keymaps/default/`
The file contents say "default keymap".
* enable Community Layouts support
* add QMK Configurator data
* touch-up `rules.mk`
James Young