If invoked 'go list' command fails, show its stderr.

	}

	cmd := exec.Command("go", "list", "-json", "./...")

	output, err := cmd.Output()

	if err != nil {

		fmt.Fprintf(os.Stderr, "Failed to dump the go packages: %v\n", err)

	var stdoutb, stderrb bytes.Buffer

	cmd.Stdout = &stdoutb

	cmd.Stderr = &stderrb

	if err := cmd.Run(); err != nil {

		fmt.Fprintf(os.Stderr, "Running %q to dump the Go packages failed: %v, stderr:\n%s\n",

			cmd.String(), err, stderrb.Bytes())

		os.Exit(1)

	}

	decoder := json.NewDecoder(bytes.NewReader(output))

	decoder := json.NewDecoder(bytes.NewReader(stdoutb.Bytes()))

	pkgs := []*GoPackage{}

	pkgMap := map[string]*GoPackage{}