CKeditor: Add class to all ul and ol elements on output
There is no reason to do that for styling purposes. You can target the ul and ol elements by their parent container. The classes depends on your theme output, but consider this for the Garland theme:

/* Style all ul and ol elements from the body output. */
#center .node .content ul,
#center .node .content ol {
  /* Styles here */
}


If you are missing classes you can add those in the page.tpl.php and node.tpl.php templates.