Tests: Replace resource loader with AMD

:boom: WIP...

Pulll request's goal is to AMDify tests for 1.12.0 release and address part of http://bugs.jqueryui.com/ticket/10119.


> I'd avdocate for either including the css with no js to handle writing the link tags

Is it feasible? dcac8c1f29cd718c949c1b2c48681a90b0f647ed replaced the plain link tags with the resourse loader, ie. this is why we have our own css injector. Unless this is not used anymore...