Help converting to 2.x

<?php

$plugin_info = array(
  'pi_name' => 'Dash Lower',
  'pi_version' => '1.0',
  'pi_author' => 'N David Brown',
  'pi_author_url' => 'http://www.buildingfrombelow.org/',
  'pi_description' => 'Replaces spaces with dashes, and converts a string to lowercase', // added a comma here
  'pi_usage' => DashLower::usage()
  );

class DashLower
{
  function DashLower()
  {
      global $TMPL;
      $this->return_data = strtolower(str_replace(' ', '-', $TMPL->tagdata));
  }

  // ----------------------------------------
  //  Plugin Usage
  // ----------------------------------------

  // This function describes how the plugin is used.
  //  Make sure and use output buffering

  function usage()
  {
  ob_start();
  ?>
    {exp:dashlower}your_text{/exp:dashlower}
  <?php
  $buffer = ob_get_contents();
  ob_end_clean();
  return $buffer;
  }
}
?>