code: function ask(question, validValues, message) {
    readline.setDefaultOptions({
      limit: validValues,
      limitMessage: message
    });
    return readline.question(question);
  }
docs: A helper function for getting user input
  @param {string} question The question to be asked
  @param {string} validValues Typically a regex or array
  @param {string} message The validation message
  @returns {string} the user input