Recommendation is to avoid using the year nomenclature as this
information is already encoded in the git repo. Avoids needing to
repeatly update.
Also updates AUTHORS.txt from current repo with contributor names
Adds the initial implementation of bezier overlay
(assistant) and geometry manager. This is only
implemented in Pcbnew - the code is common, but
eeschema doesn't currently use it for any shape.
Relates-To: https://gitlab.com/kicad/code/kicad/-/issues/8828
