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 occasionally get `30. Called start() while already started (QUnit.config.semaphore was 0 already)` after `29. Both - hidden on second button click` (expand above). @jzaefferer any idea how to fix this?