Fix commandline parsing and flake8 findings, rebase

Fixed commandline and config parsing. Thx @xplusplus.
Rebased on master and fixed merge conflicts.

Major rework, no regex/globbing, more walking

Instead of using regexes and globbing to find the rules.mk and keymap.c
files, walk the directory tree to find them.
Also, do away with the concept of revision.

Fix merging community and base keymaps

Return only the unique keymaps

Drop bs4 dependency, update docs, minor improvements

Fix regex for parsing rules.mk files

I don't know why it couldn't put it together before... ¯\_(ツ)_/¯

Add test for list_keymaps

Another major refactoring, add documentation

Move all useful functions to the qmk module and use the cli subcommand
as a wrapper around it.
Add both inline comments and documentation.

Fix output format

Try to figure out revision, drop -rv/--revision argument

Fix help message.

Get all buildable keymaps for each revision

The command now return all keymaps that's buildable for a
keyboard/revision. If the base directory of a keyboard does not contain
a 'rules.mk' file, nothing is returned. If the base directory contains a
'keymaps' directory, those keycaps will be returned for every revision.

Major update to work better with revisions

Find the community keymaps supported by each revision.

Add bs4 to requirements.txt

UnicodeDammit is needed from bs4 for reading files.

CLI: add support for list_keymaps

List all the available keymaps for a given keyboard

Adding VIA support for 40percentclub/luddite (#8158)

* Adding VIA support for 40percentclub/luddite

* Update config.h

* Update rules.mk

* Delete config.h

config.h was created to override the "default" of RGBLED_NUM 8
deleting the file to keep with defaults

* Removing block and comment as suggested

* Update PRODUCT_ID

Changing from:

 #define PRODUCT_ID      0x0A0C 

To:

 #define PRODUCT_ID      0x4C55 // "LU"

* Changing Vendor ID

Changing Vendor ID from:
#define VENDOR_ID       0xFEED
To:
#define VENDOR_ID       0x3430 // "40"

[keymap] Update audio controls on community (#8163)

* Update audio controls on community

* Add rules for various boards

* TKL support

Just60 Configurator layout support and thinxer keymap (#7761)

* Just60 Configurator layout support

* adds thinxer keymap, which is the default keymap with QMK DFU bootloader

Add community layout support to Mysterium (#8164)

Convert two handwired default keymaps to Dynamic Macro feature (#8166)