Conflicts:
	modules/cudaoptflow/perf/perf_optflow.cpp
	modules/cudaoptflow/src/tvl1flow.cpp
	samples/gpu/stereo_multi.cpp

Consider this a part of merging #1357.

Conflicts:
	modules/contrib/src/retina.cpp
	modules/gpu/perf/perf_video.cpp
	modules/gpuoptflow/src/tvl1flow.cpp
	modules/ocl/include/opencv2/ocl/ocl.hpp
	modules/ocl/perf/perf_calib3d.cpp
	modules/ocl/perf/perf_color.cpp
	modules/ocl/perf/perf_match_template.cpp
	modules/ocl/src/precomp.hpp
	samples/gpu/stereo_multi.cpp

cudev is used for new device layer