Enable Safe shutdown and reboot w/Splash screens

This should help elminate disk corruption IF people use menu items for shutdown.
Modified S95xbmc to shutdown disks, flush information, etc before reboots or power down.
Added some splash screens to better keep user informed about what is going
 on at boot/shutdown and to let them know when save to turn off device.

Note: for this patch to have benefit to M3, xbmc must be modified so shutdown = true for the M3.