Add additional versions of jQuery to the tests directory and link to them in index.html
In jQuery 1.9+, when expecting a JSON return value, it is now an error to return an empty string.
In jQuery 1.9+, AJAX events must be attached to the document.
In jQuery 1.9.1+, responseXML is processed differently, mockjax needs to fill responseText with this XML string.
In jQuery 2.0+, xhr.onreadystatechange has been renamed to xhr.onload.