positional arguments must appear at the end of the description array
(after the last option) and should have a metavar set and not have
shortname or longname. Simple, elegant and fit :-)
There is a new function to parse the positional arguments,
ecore_getopt_parse_positional() because we may want to not try to
parse them in the case of a quit-option such as --help, --license,
--copyright, --version or some user-defined action. This avoids us
producing errors of missing positional arguments when printing help
and adds some flexibility as well.
This should make Tasn happy :-)