beeversion: Complete rewrite

new features:
beeversion is now able to handle more then one extraversion.
beesort now honors '-' < '_' in pkgname vs. pkgname_pkgextraname.

removed features:
--filter-pkgfullname was removed.
bee_version_parse: inline all static mini-functions
bee_version_parse: pkgname must start with an alphabetic character
beeversion: minor cleanup and date fix
beeversion: parse cmd xxx