Add some documentation to the transform

[LesML] / TESTING / 📤 / comments-continuations

<?xml version="1.0"?>
<div xmlns="http://www.w3.org/1999/xhtml"><article lang="en" xml:lang="en"><div class="body"><div data-level="1"><p>This continues nothing.</p></div><div><!-- This is a comment.
It can extend over multiple lines.--><p>Here is a continuation of the div containing the comment.</p><p>It keeps going on.</p></div></div></article></div>