Upgraded requirejs and updated readme

Changed: upgraded requirejs to 2.1.9 so I could configure it to
ignore/skip inserting semicolons between modules since that broke
jshint when they were done needlessly.

Also updated README to include kitchensink build option.
Huge refactor of AJAX + suport for JSONP

Changed: refactores AJAX code into separate files to make it more
manageable. Also added basic support for JSONP (missing: specifying
callback names).