Some docs improvements (#15845)

* docs: clarify in "Keymap Overview" what LAYOUT is and isn't

It is not strictly necessary to use LAYOUT macros in keyboard.c, but it
is a convenient abstraction of hardware internals, allowing focus on the
physical keyboard layout.

From the C source point of view LAYOUT is macro with a parameter list,
which expands to a array of rows that each is an array with a keyboard
scancode for each column. A macro parameter list is not an array, and
even less a single array.

Perhaps no big deal, but also no reason to give incorrect hints.

* docs: update "Understanding QMK's Code" to current code structure introduced in 96e2b13d1de

This part of the documentation was no longer correct. I tried updating
it, mainly copy editing and using github links to latest release.

This is not trying to fix all problems, but just trying to fix some
problems while reusing much of the old phrases and structure.

* Update docs to use "qmk format-python"

1 files changed, 2 insertions, 2 deletions

diff --git a/docs/cli_development.md b/docs/cli_development.md
index 62be3b3d8c..17370a732a 100644
--- a/docs/cli_development.md
+++ b/docs/cli_development.md
@@ -188,7 +188,7 @@ cli.log.info('Reading from %s and writing to %s', cli.args.filename, cli.args.ou
 
 # Testing, and Linting, and Formatting (oh my!)
 
-We use nose2, flake8, and yapf to test, lint, and format code. You can use the `pytest` and `format-py` subcommands to run these tests:
+We use nose2, flake8, and yapf to test, lint, and format code. You can use the `pytest` and `format-python` subcommands to run these tests:
 
 ### Testing and Linting
 
@@ -196,7 +196,7 @@ We use nose2, flake8, and yapf to test, lint, and format code. You can use the `
 
 ### Formatting
 
-    qmk format-py
+    qmk format-python
 
 ## Formatting Details