Made WinJS amd modules free of global WinJS

Made WinJS amd modules free of global WinJS, now the wrappers (WinJS.js, base.js, ui.js) are the only things which publish the WinJS global, this enables SxS WinJS.
Since factory returns nothing now, if they are including this file and using AMD they won't get a reference to the WinJS global. That doesn't seem awesome, especially since you just did all the work to make it function side-by-side.