Added a Makefile for tracking versions of gotree

Makefile

@@ -0,0 +1,15 @@
+GO_EXECUTABLE := go
+VERSION := $(shell git describe --abbrev=10 --dirty --always --tags)
+DIST_DIRS := find * -type d -exec
+
+all: build install
+
+build:
+	${GO_EXECUTABLE} build -o gotree -ldflags "-X github.com/fredericlemoine/gotree/cmd.Version=${VERSION}" github.com/fredericlemoine/gotree
+
+
+install:
+	${GO_EXECUTABLE} install -ldflags "-X github.com/fredericlemoine/gotree/cmd.Version=${VERSION}" github.com/fredericlemoine/gotree
+
+test:
+	${GO_EXECUTABLE} test github.com/fredericlemoine/gotree/tests/

cmd/version.go

@@ -0,0 +1,53 @@
+// Copyright © 2016 NAME HERE <EMAIL ADDRESS>
+//
+// 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 cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+var Version string
+
+// versionCmd represents the version command
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "A brief description of your command",
+	Long: `A longer description that spans multiple lines and likely contains examples
+and usage of using your command. For example:
+
+Cobra is a CLI library for Go that empowers applications.
+This application is a tool to generate the needed files
+to quickly create a Cobra application.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Println(Version)
+	},
+}
+
+func init() {
+	RootCmd.AddCommand(versionCmd)
+
+	// Here you will define your flags and configuration settings.
+
+	// Cobra supports Persistent Flags which will work for this command
+	// and all subcommands, e.g.:
+	// versionCmd.PersistentFlags().String("foo", "", "A help for foo")
+
+	// Cobra supports local flags which will only run when this command
+	// is called directly, e.g.:
+	// versionCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+
+}