Initial version.

Basic command line parameter support. Parsers for the current Microsoft
conventions, the older MS-DOS/Command prompt conventions and for
POSIX/GNU style conventions. Provision is also made for a user defined
parser.

Simple command line parameters are supported, as are custom commands
(like the MS NET command). Usage text can be generated using
descriptions provided as part of the command configuration.

Command line parameters are configured with a fluent interface, but it
doesn't make perfect sense and needs refactoring.