* refactor default keymap
- shorten layer names
- KM_QWERTY -> _QW
- KM_MEDIA -> _MD
- KM_GUI_LOCK -> _GL
- use QMK-native keycode aliases
- use four-space indent
- grid-align keycodes
* remove third layer from default keymap
The third layer only serves to disable the GUI keys, which we can do with a keycode.
* update default keymap readme
* ghost_squid.h: add matrix diagram
* add LAYOUT_fullsize_ansi
* add LAYOUT_fullsize_iso
* use LAYOUT_fullsize_iso macro in default keymap
Refactor the default keymap to use the new LAYOUT_fullsize_iso macro.
* remove LAYOUT macro
Same matrix as LAYOUT_fullsize_iso, but in a different assignment order.
* enable Community Layout support
