"quirks mode"

quirks mode: allows any options to be passed at runtime. 
See below and issue #14.
     /**
     * "quirks mode" is referenced in issue #14, as the preferred  
     * method to allow undefined options to be accepted instead
     * of throwing an Exception (default behavior). To enable, 
     * Getopt->setQuirksMode(true) before calling Getopt->parse().
     * During run-time, all option strings will be accepted and added to
     * the list of acceptable options if not already there.
     * TODO: in the future it would be nice to be able to toggle different 
     * settings for quirks mode.
     * @link https://github.com/ulrichsg/getopt-php/issues/14
    */