(#19761) Added virtual and is_virtual fact on Windows

Without this patch, the virtual and is_virtual fact is not set on Windows computers. This patch fixes the problem, giving an initial coverage for some hypervisors.

The solution proposed is based on the manufacturer and model properties from WMI object Win32_ComputerSystem. This first version is able to detect the following systems: HyperV, VirtualBox, Vmware and KVM.