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/hnsglobals.go

@@ -0,0 +1,16 @@
+package hcsshim
+
+import (
+	"github.com/Microsoft/hcsshim/internal/hns"
+)
+
+type HNSGlobals = hns.HNSGlobals
+type HNSVersion = hns.HNSVersion
+
+var (
+	HNSVersion1803 = hns.HNSVersion1803
+)
+
+func GetHNSGlobals() (*HNSGlobals, error) {
+	return hns.GetHNSGlobals()
+}