code: function makeRandomId(digits) {
      digits = digits || 16;
      var id = "";
      for (var ii = 0; ii < digits; ++ii) {
        id = id + ((Math.random() * 16 | 0)).toString(16);
      }
      return id;
    }
docs: Creates a random id
  @param {number} [digits] number of digits. default 16