Description:
------------
session_set_save_handler expects callbacks to session handler's operations (open, close, etc). It would be great if this function accepts a core's session handler interface. Something like:

<?php
interface Session_Handler_Interface {
    function open();
    function close();
    function read();
    function write();
    function destroy();
    function gc();
}

class Some_Handler implements Session_Handler_Interface {
    // implementations ....
}

$handler = new Some_Handler();
session_set_save_handler($handler);

Then, we'll have an OOP approach too. The old one should not be removed.

Thank you.