fix oembed for non-successful requests.

js/babl/public/index.html

				var xhr = new XMLHttpRequest();
				xhr.open('GET', oembedEndpoint + '?format=json&maxwidth=450&url=' + url);
				xhr.onreadystatechange = function() {
					if (xhr.readyState == XMLHttpRequest.DONE) {
						console.log(url, xhr.status);
					if (xhr.readyState == XMLHttpRequest.DONE && xhr.status == 200) {
						var tmpEl = document.createElement('div');
						tmpEl.innerHTML = JSON.parse(xhr.responseText).html;
						el.parentElement.replaceChild(tmpEl.firstChild, el);