Add Microsoft X-Box pad v2
This is a binding for the original X-Box Controller S. It is very similar
to the X-Box 360 controller with the following differences:

 * No L/R Shoulder buttons. These are mapped to White and Black
   (under right thumb) respectively.

 * No Guide button. There are no more spare buttons.

Contributed by ali1234, I had to fix a missing comma at the end.