php and syntax error (and expanded readme?)

Here's a patch to fix a PHP E_ALL notice and a syntax error.

I downloaded this to get a better idea of what it does (seems cool) and tried to just form_alter the comment form to have $form['#ajaxsubmit'] = TRUE; but it didn't seem to impact my comment submission form. Perhaps that is expected, but it seemed weird to me. I would love to see an example of how this is used with core.