* Drop usage of gcc2, as no supported Python version uses it.
(but provide "non _x86" on 32 bits).
* Drop support for Python 3.8 (no in-tree usage, other than a
disabled recipe (will work on that later).
* Build with build/installer.
* All test pass OK for the supported Python versions.
x86_64 is used as a baseline: the "x86_64" entry, whatever status it has,
is transformed into "all", and then the other entries in ARCHITECTURES
either dropped or rearranged appropriately.
