code: public function render()
      {
          $tab_stop = $this->longestFlag($this->flag_sets) + 4;
          $text     = $this->overview . "\n";
          $numberOfFlags = count($this->flag_sets);
          for ($i = 0; $i < $numberOfFlags; $i++) {
              $text .= $this->renderFlagSet($this->flag_sets[$i], $this->explanations[$i], $tab_stop);
          }
  
          return $this->noDuplicateNewLines($text);
      }
docs: Generates the help text.
  
  @returns string      The complete formatted text.