Removed clearing of langLoaderCreated, since this is now done in yui.preloadResourceVersions.
Updated history.
Not returning invalid yui modules through parseResourceVersions; making sure not to call YUI.add twice on a module, since mojito will use the first one and so the module should not be replaced.
Mocking store.YUI object.
Creating runtime YUI object in preloadResourceVersions such that store.preload can be called multiple times without errors. YUI object is created in a sandbox.