Remove windows files

Windows is not going to use containerd because there is already a
similar implementation on windows.  This removes all the windows files
because there is no reason to keep this overhead when its not going to
be used.

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

osutils/windows.go

@@ -1,9 +0,0 @@
-// +build windows
-
-package osutils
-
-// GetOpenFds returns the number of open fds for the process provided by pid
-// Not supported on Windows (same as for docker daemon)
-func GetOpenFds(pid int) (int, error) {
-	return -1, nil
-}