[CLI] Add c2json (#8817)

* Basic keymap parsing finally works

* Add 'keymap.json' creation to the qmk.keymap module

* Add tests and fix formatting

* Fix/exclude flake8 errors

* Convert keymap.c to valid keymap.json

* Fix some errors

* Add tests

* Finalize keymap.json creation, add json template

* Add docs

* Move pygments to the standard requirements

* Add support for nameless layers, fix tests

* Fix things after rebase

* Add missing 'keymap' value.

* Fix missing layer numbers from advanced keycodes

Buckwich noticed that if the advanced keycode / layer toggling key
contains a number, it goes missing.
Now we properly handle them.
Thx for noticing!

* Apply suggestions from code review

* fixup tests

Co-authored-by: Zach White <skullydazed@drpepper.org>
Co-authored-by: skullY <skullydazed@gmail.com>

lib/python/qmk/cli/__init__.py

@@ -6,6 +6,7 @@ import sys
 
 from milc import cli
 
+from . import c2json
 from . import cformat
 from . import compile
 from . import config