Split up autoconf/version-numbers and move it to conf dir

The file make/autoconf/version-numbers is plagued by a two-fold problem: first of all, it's a configuration file, not a part of autoconf, so it should reside in make/conf instead of make/autoconf.

Secondly, contrary to the name, it does not only contain version numbers, but also the branding properties (company name, product name, etc). This should be split out into a separate branding configuration file.