Merge branch 'master' into gpu-cuda-rename

Merge branch 'master' into gpu-cuda-rename

Conflicts:
	modules/core/include/opencv2/core/cuda.hpp
	modules/cudaimgproc/src/gftt.cpp
	modules/objdetect/include/opencv2/objdetect/erfilter.hpp
	modules/objdetect/src/erfilter.cpp
	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