Compensate for missing "lang" attribute

If the "lang" attribute is missing from the <html> element it breaks the engine.
Defaults to nothing in lieu of using "en" as default.
Update to latest version of jQuery

By "latest" version I mean the latest older-browser-compatible version (v1.11.0)
and not the bleeding-edge version (v2.1.0).
Merge pull request #22 from michaelenger/master

Update jQuery to version 1.11.0