Add (optional?) unrecognized-option parser

The logic for parsing will be something like

while (the input is not empty):
    parser := selectParser(context)
    if (parser):
        result = parser(context)
        if (result.error):
            handleError(result.error)
            return
        context = result.context
        continue
    result = parseArguments(context)
    if (result.error):
        handleError(result.error)
        return
    context = result.context

Add support for raising an error when an argument comes in the shape of an unknown option. This should be disabled when the "--" is encountered