Add build-containerd.sh to build containerd from existing repo

Signed-off-by: Lantao Liu <lantaol@google.com>

hack/test-e2e-node.sh

@@ -59,6 +59,12 @@ fi
 GOPATH=${GOPATH%%:*}
 
 # Get kubernetes
+from-vendor KUBERNETES k8s.io/kubernetes
+# k8s.io is actually a redirect, but we do not handle the go-import
+# metadata which `go get` and `vndr` etc do. Handle it manually here.
+if [ x"$KUBERNETES_REPO" = "xk8s.io" ] ; then
+  KUBERNETES_REPO="https://github.com/kubernetes/kubernetes"
+fi
 KUBERNETES_PATH="${GOPATH}/src/k8s.io/kubernetes"
 if [ ! -d "${KUBERNETES_PATH}" ]; then
   mkdir -p ${KUBERNETES_PATH}