def list_flag_option(name, description, **config)
      add_option Clin::OptionList.new(name, description, **config.merge(argument: false))
    end
def list_flag_option(name, description, **config)
      add_option Clin::OptionList.new(name, description, **config.merge(argument: false))
    end
Add a list options that don't take arguments
 Same as .list_option but set +argument+ to false
 @see Clin::OptionList#initialize