code: public function render(OptionCollection $options)
      {
          # echo "* Available options:\n";
          $lines = array();
          foreach ($options as $option) {
              $c1 = $this->renderOption($option);
              $lines[] = "\t".$c1;
              $lines[] = wordwrap("\t\t".$option->desc, $this->screenWidth, "\n\t\t");  # wrap text
              $lines[] = '';
          }
  
          return implode("\n", $lines);
      }
docs: render option descriptions.
  
  @return string output