highgui project: added file cap_winrt.hpp
highgui.hpp: added CAP_PROP_WINRT_START_DEVICE property
highgui_c.h: removed CV_CAP_WINRT (and C interface)
cap.cpp: removed C interface, added C++ interface, added include "cap_winrt.hpp"
precomp.hpp: removed C interface: cvCreateCameraCapture_WinRT(int index)
MainPage.xaml.cpp: added comment: C++ extern will not work across DLLs - must use dllimport
cap_winrt.hpp: added new file: C++ interface for video capture
cap_winrt.cpp: refactored C interface for C++: class VideoCapture_WinRT : public IVideoCapture
main.cpp: start device on main thread, do cam >> frame on image proc (bg) thread - RUNS OK