[RFC] [wwwdocs] Rewrite docs on commit message and patch format

[Jakub Jelinek]

On Tue, Jun 15, 2021 at 09:24:44AM -0500, Segher Boessenkool wrote:
> IMNSHO this all should emphasise *why* these things are recommended, and
> don't pretend these are "rules" at all.  They are not.  The important

Many of them actually are rules.
Everything that is verified by the pre-commit hook and commits rejected if
the hook reports some rule not being fulfilled.

	Jakub