text: function iso8601(date) {
    return date.getUTCFullYear()
      + "-" + (date.getUTCMonth()+1)
      + "-" + date.getUTCDate()
      + "T" + date.getUTCHours()
      + ":" + date.getUTCMinutes()
      + ":" + date.getUTCSeconds() + "Z";
  }
  
  document.querySelector('.load_time').setAttribute('datetime', iso8601(new Date()));
  var timeagoInstance = new timeago(null, navigator.language.replace('-', '_'));
  timeagoInstance.render(document.querySelectorAll('.need_to_be_rendered'));
  
  // 2. demo
  document.getElementById('demo_now').innerHTML = new timeago().format(new Date());
  document.getElementById('demo_20160907').innerHTML = new timeago(null, 'zh_CN').format('2016-09-07');
  document.getElementById('demo_timestamp').innerHTML = new timeago().format(1473245023718); 