[RFC] Add a second argument to callback of preg_replace_callback

Hey: I thought it is a minor change, so was not plan to make a RFC .. but since there are some insistent objections, I think a RFC is better. let's people vote for it. here is the RFC: https://wiki.php.net/rfc/second_arg_to_preg_callback and objections are also listed. thanks -- Laruence Xinchen Hui http://www.laruence.com/