Merge commit '43aec5ad' into merge-2.4

Conflicts:
	cmake/OpenCVConfig.cmake
	cmake/OpenCVLegacyOptions.cmake
	modules/contrib/src/retina.cpp
	modules/gpu/doc/camera_calibration_and_3d_reconstruction.rst
	modules/gpu/doc/video.rst
	modules/gpu/src/speckle_filtering.cpp
	modules/python/src2/cv2.cv.hpp
	modules/python/test/test2.py
	samples/python/watershed.py

modules/flann/include/opencv2/flann/random.h

@@ -131,5 +131,3 @@ public:
 }
 
 #endif //OPENCV_FLANN_RANDOM_H
-
-

modules/flann/include/opencv2/flann/result_set.h

@@ -540,4 +540,3 @@ private:
 }
 
 #endif //OPENCV_FLANN_RESULTSET_H
-