Add Windows support

[lxp]

Currently, there are a few issues, why cfv including the test suite does not run on Windows. We have to investigate the issues and fix them.

[lxp]

I consider shifting back Windows support to a later release. If anyone wants to use cfv on Windows, please speak up.

[luckyluca]

I’d love to use it on Windows 10 to check and maintain data integrity on my 3 external usb backup hdds.

Please let me know if I could help testing anything.
thanks