Introduce containerd-shim-runhcs-v1 on Windows

Implements the containerd-shim-runhcs-v1 shim on Windows for the runtime
v2 shim API.

Signed-off-by: Justin Terry (VM) <juterry@microsoft.com>

vendor/github.com/Microsoft/hcsshim/version.go

@@ -2,6 +2,5 @@ package hcsshim
 
 // IsTP4 returns whether the currently running Windows build is at least TP4.
 func IsTP4() bool {
-	// HNSCall was not present in TP4
-	return procHNSCall.Find() != nil
+	return false
 }