Upgraded to TypeScript v1.0 from pre-release versions. Switched type definition files for WinJS and WinRT to NuGet packages to get regular updates.

Conflicts:
	KhanAcademy/pages/mainHub/mainHub.ts
	KhanAcademy/pages/videoPage/videoPage.ts
Merge pull request #109 from anprak/win8.0

TypeScript upgrade for Win8.0 branch