code: function loadPulse() {
  	const pulseUrl = '/build/pulse.svg';
  	const xhr = new XMLHttpRequest();
  	const timestamp = (new Date())
  			.toISOString()
  			.slice(0, 10)
  		;
  	xhr.open('GET', pulseUrl + '?' + timestamp);
  	xhr.onload = function() {
  		if (xhr.status === 200) {
  			onPulseLoaded(xhr.responseText);
  		}
  	};
  	xhr.send();
  }
docs: Author: Artem Sapegin, http://sapegin.me, 2015