Fix regression issue for IE and older discovered at https://github.com/MoOx/pjax/pull/16/commits

index.js

@@ -81,7 +81,7 @@ Pjax.prototype = {
   },
 
   loadContent: function(html, options) {
-    var tmpEl = document.implementation.createHTMLDocument()
+    var tmpEl = document.implementation.createHTMLDocument("")
 
     // parse HTML attributes to copy them
     // since we are forced to use documentElement.innerHTML (outerHTML can't be used for <html>)