remove dependency on CinderMain.h
AppImplMswRendererDx is "short circuited" where needed to keep DX XAML framework in charge of DX lifecycle
allowing normal instantiation of AppImplMswRendererDx
AppImplWinRTBasic::runReady is "short circuited" to use DX XAML framework render loop with timer
call AppImplWinRTBasic::runReady to get full initialization
emit Window::resize event properly