[pkg] Configure "universal" wheel build According to https://packaging.python.org/distributing/#wheels, we should create universal wheels (no 2to3 step, no C extension). Configure this in setup.cfg. [ci skip]

etc/init.d
etc/cubicweb.d
etc/bash_completion.d
usr/bin
usr/share/doc/cubicweb-ctl
var/log/cubicweb
var/lib/cubicweb/backup
var/lib/cubicweb/instances