function fibonacciBackOff(attempt) {
  return (fibonacci(attempt) * 1000) + 5000;
}
Strategy for reconnection that backs off with the fibonacci pattern.  It is
offset by 5 seconds so the first attempt will happen after 5 seconds.
@param {number} attempt The number of reconnects since the last connection.
@return {number} The amount of time to the next reconnect, in milliseconds.