The ARRAY_AXIS class now accepts lowercase letters (a-z) as input for
alphabetic numbering schemes and preserves that case in the output.
This allows users to create pin numbers like a1, b1, c1 which are
commonly used in DIN 41612 and other backplane connectors.
Fixes https://gitlab.com/kicad/code/kicad/-/issues/22787
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
Primary increment is the right most bit, secondary is the next
rightmost. So you can increment 'A1' to 'A2' or 'B1' with
Shift-Alt-Scroll and Ctrl-Alt-Scroll respectively.
Remove the axis numbering code from ARRAY_OPTIONS
and place in a new class, ARRAY_AXIS. This keeps
the logic for the array item numbering separate from
the logic for the array item geometry.
This simplifies the logic in the ARRAY_OPTIONS class, which
no longer has to deal with the numbering of each axis.
Seth Hillbrand