Moodle 2.4 fixes(js and rendering related)

Hi,

I've made a few changes to get the order question type working in Moodle 2.4.

I've changed renderer.php to call $PAGE->requires->js_init_call(...) in order to include order.js and its dependencies instead of $PAGE->requires->yui2_lib(...) which is now officially not working anymore. I've also changed order.js to use YUI 2in3.

If you have any questions, please don't hesitate!

Regards,

François Moreau