Merge remote-tracking branch 'origin/2.4' into merge-2.4

Conflicts:
	modules/core/include/opencv2/core/version.hpp
	modules/ocl/include/opencv2/ocl/ocl.hpp
	modules/ocl/src/initialization.cpp
	modules/ocl/test/main.cpp
	modules/superres/CMakeLists.txt
	modules/superres/src/input_array_utility.cpp
	modules/superres/src/input_array_utility.hpp
	modules/superres/src/optical_flow.cpp