highgui: Support to change trackbar count in setTrackbarPos and replaced deprecated CreateToolbarEx in Windows.

- disabled doxygen tree
- enabled doxygen enum listing
- added imgproc reference to main page
- enabled BiB support
- chenged doxygen root page format

Add depends from highgui to imgcodecs and videoio. And include header from imgcodecs and videoio to imgcodecs

Fixed constant value for focus mode FOCUS_MODE_CONTINUES_PHOTO;
Add setters and getters for exposure lock and white balance lock flags;
Excluded camera restart for all setters except frame size.

Move declaration of IVideoCapture class into precomp.hpp, make some methods of IVideoCapture pure virtual

Remove implementation of CvCapture interface for Intel PerC camera. Add IVideoCapture interface and implementation of this one for Intel PerC camera

To be used in the mouse callback like this:
    if (CV_EVENT_MOUSEWHEEL == CV_GET_MOUSEWHEEL_EVENT(event))
    {
       int delta= CV_GET_WHEEL_DELTA(event);
       // use delta...
    }

Added "PVAPI_" prefix to FrameStartTriggerMode definition

Conflicts:
	modules/core/include/opencv2/core/cuda.hpp
	modules/cudacodec/src/thread.cpp
	modules/cudacodec/src/thread.hpp
	modules/superres/perf/perf_superres.cpp
	modules/superres/src/btv_l1_cuda.cpp
	modules/superres/src/optical_flow.cpp
	modules/videostab/src/global_motion.cpp
	modules/videostab/src/inpainting.cpp
	samples/cpp/stitching_detailed.cpp
	samples/cpp/videostab.cpp
	samples/gpu/stereo_multi.cpp

Windows RT sample cleanup.
Video I/O code cleanup.

Bug in Video for Windows capture init fixed;
Media Foundation based capture finalization fixed;
Highgui tests for video i/o updated.

Updated iOS camera. Added rotation flag. Added functions to lock/unlock focus, white balance and exposure.