when shutting down: ReactOS just cuts the power instead of powering down sata hdds first

When I shut down ReactOS it seems as the operating system does not send a signal to the hard drive to power off. Maybe it does but then doesn't wait till this is done. It seems as it simply cuts the power.

My hard disc makes a terrible noise when ReactOS cuts the power. Maybe this is harmful to the device.

I increased the priority by 1 step to "critical" because I think that possible physical damage to the system should be addressed with priority.

tested on 0.4.7 RC1