code: function appendComments(comments, ul) {
      $.each(comments, function() {
        var div = createCommentDiv(this);
        ul.append($(document.createElement('li')).html(div));
        appendComments(this.children, div.find('ul.comment-children'));
        // To avoid stagnating data, don't store the comments children in data.
        this.children = null;
        div.data('comment', this);
      });
    }
docs: Recursively append comments to the main comment list and children
  lists, creating the comment tree.