
Let's try to consolidate our documentation in doc/ in the repo. This includes some documentation from README.md, the HACKING.md coding style and the gitlab wiki. The README.md file now links to all top-level topics (i.e. not reachable via other topics). This also includes a few small changes to make things more consistent. Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3465>