code: public OptionBuilder withShortForm( String shortForm )
      {
          if (option.getShortForm() != null) throw new IllegalArgumentException( "Short form given twice" );
          option.setShortForm( shortForm );
          return this;
      }
docs: <p>withShortForm.</p>
  
  @param shortForm a {@link java.lang.String} object.
  @return a {@link com.greenpepper.util.cli.OptionBuilder} object.