Use protoversion for containerd version

Signed-off-by: Peter Edge <peter.edge@gmail.com>

ctr/version.go

@@ -0,0 +1,22 @@
+package main
+
+import (
+	"fmt"
+
+	"go.pedge.io/proto/version"
+
+	"github.com/codegangsta/cli"
+	"github.com/docker/containerd"
+)
+
+var VersionCommand = cli.Command{
+	Name:  "version",
+	Usage: "get the containerd version",
+	Action: func(context *cli.Context) {
+		serverVersion, err := protoversion.GetServerVersion(getClientConn(context))
+		if err != nil {
+			fatal(err.Error(), 1)
+		}
+		fmt.Printf("Client: %s\nServer: %s\n", containerd.Version.VersionString(), serverVersion.VersionString())
+	},
+}