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/video/src/bgfg_gaussmix.cpp

@@ -470,4 +470,3 @@ Ptr<BackgroundSubtractorMOG> createBackgroundSubtractorMOG(int history, int nmix
 }
 
 /* End of file. */
-

modules/video/src/kalman.cpp

@@ -127,5 +127,3 @@ const Mat& KalmanFilter::correct(const Mat& measurement)
 }
 
 };
-
-

modules/video/src/lkpyramid.hpp

@@ -34,4 +34,3 @@ namespace detail
 
 }// namespace detail
 }// namespace cv
-

modules/video/src/simpleflow.cpp

@@ -685,4 +685,3 @@ CV_EXPORTS_W void calcOpticalFlowSF(InputArray from,
 }
 
 }
-