<ol class="tree">
      <li>
        <label>folder0/folder1/folder2</label> <input type="checkbox" checked />
        <ol>
          <li class="file"><a href="0">0</a></li>
      <li>
        <label>folder3</label> <input type="checkbox" checked />
        <ol>
          <li class="file"><a href="1">1</a></li>
        </ol>
      </li>
        </ol>
      </li>
      <li>
        <label>folder4</label> <input type="checkbox" checked />
        <ol>
          <li class="file"><a href="2">2</a></li>
</ol>