message: build(aio): add div with class around content
  Closes
diff: -{% if doc.title %}<h1>{$ doc.title $}</h1>{% endif %}
  +{% if doc.title %}<h1>{$ doc.title | marked $}</h1>{% endif %}
  +<div class="content">
  {$ doc.description | marked $}
  +</div>
  \ No newline at end of file
  