HAL extensions: added initial version of universal intrinsics (C implementation and SSE2, NEON - TBD). added empty files where some functionality from core and imgproc will be moved to

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

also refactored VideoSource interface (made it simplier, now it has only 2 abstract methods)

This reverts commit fba72cb6, reversing
changes made to 02131ffb.

2) NVidia tests for GPU
3) FD sample that uses NVidia's interface.