add(cli): cli interface for push, pull and version

cmd/version.go

@@ -0,0 +1,20 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+func init() {
+	rootCmd.AddCommand(versionCmd)
+}
+
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Print the version of gitwarrior",
+	Long:  `All software has versions. This is gitwarrior's`,
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Println("v0.1")
+	},
+}