Updated the windows 8 demo

Hi Paul,
Just wanted to say great project.  I've only just started looking into the project and whilst I was at it I though I would add a bit to the windows 8 demo help me learn a bit more about the project.  So I added a settings pane, command bar and a zoom slider to the windows 8 demo.  Not 100% sure if I have the best way of doing the zoom so if I need to make any changes to get this accepted please let me know.

Regards
Martin