Add version command

Author: Sazon, John Bryan J

cmd/root.go

@@ -58,9 +58,8 @@ The login token will be saved in $HOME/.gitlabctl.yaml file.
 
 // rootCmd represents the base command when called without any subcommands
 var rootCmd = &cobra.Command{
-	Version: "alpha",
-	Use:     "gitlabctl",
-	Short:   "Gitlab command-line interface",
+	Use:   "gitlabctl",
+	Short: "Gitlab command-line interface",
 	Long: `gitlabctl is a Gitlab client for the command-line.
 
 This client helps you view, update, create, and delete Gitlab resources from the 

cmd/version.go

@@ -0,0 +1,41 @@
+// Copyright © 2018 github.com/devopsctl authors
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+const version = "v0.2.0"
+
+var versionCmd = &cobra.Command{
+	Use:  "version",
+	Long: "Shows gitlabctl version",
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Println("gitlabctl version: ", version)
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(versionCmd)
+}