def flag_option(name, description, **config, &block)
      add_option Clin::Option.new(name, description, **config.merge(argument: false), &block)
    end
def flag_option(name, description, **config, &block)
      add_option Clin::Option.new(name, description, **config.merge(argument: false), &block)
    end
For an option that does not have an argument
 Same as .option except it will default argument to false
 ```
   option :verbose, 'Use verbose' #=> -v --verbose will be added to the option of this command
 ```