Using indent plugin together with Unordered list

[fdverwoerd]

When you use the ordered list button and then click on indent it generates wrong html;

The indented ul should be inside an li element.

See it here on latest version:
https://codepen.io/Wonky/pen/ZYQGaEp

Output example:

<ul>
      <li>I've making a list</li>
      <li>then pressing enter</li>
      <strike>This is wrong:</strike>
      <ul>
        <li>then using indent</li>
        <li>and create some parts</li>
      </ul>
      <li>indent back again and output is wrong.</li>
    </ul>

p.s. should be the same for ordered list.