Create a parser description and give it the parameters, that's it. You
can store values (automatically converting types!), count occurrences,
make it true or false, create a list, choose from a list of items or
even specify your own callback to process arguments!
It was inspired by Python's optparse: http://www.python.org/doc/2.5.2/lib/module-optparse.html
SVN revision: 37781