[pkg] Drop NO_SETUPTOOLS option
setuptools is the defacto standard nowadays. The only place where
NO_SETUPTOOLS option was used is during packaging (RPM, Debian) and even in
this context, it seems that setuptools is the way to go
(see https://wiki.debian.org/Python/LibraryStyleGuide).
[debian] update cubicweb-dev.lintian-overrides
cubicweb/skeleton/debian/rules.tmpl is now cubicweb/skeleton/debian/rules
prevent lintian from complaining