Added version command

version.go

@@ -0,0 +1,40 @@
+// Copyright © 2017 Max Goltzsche
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+	"fmt"
+
+	"github.com/mgoltzsche/ctnr/cmd"
+	"github.com/spf13/cobra"
+)
+
+var (
+	version    = "dev"
+	commit     = "none"
+	date       = "unknown"
+	versionCmd = &cobra.Command{
+		Use:   "version",
+		Short: "print version",
+		Long:  `print version.`,
+		Run: func(_ *cobra.Command, args []string) {
+			fmt.Printf("version: %s\ncommit: %s\ndate: %s\n", version, commit, date)
+		},
+	}
+)
+
+func init() {
+	cmd.RootCmd.AddCommand(versionCmd)
+}