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

include/CMakeLists.txt

@@ -5,5 +5,3 @@ install(FILES ${old_hdrs}
 install(FILES "opencv2/opencv.hpp"
     DESTINATION ${OPENCV_INCLUDE_INSTALL_PATH}/opencv2
     COMPONENT main)
-
-

include/opencv/cv.h

@@ -73,4 +73,3 @@
 #endif //CV_IMPL
 
 #endif // __OPENCV_OLD_CV_H_
-

include/opencv/cxeigen.hpp

@@ -46,4 +46,3 @@
 #include "opencv2/core/eigen.hpp"
 
 #endif
-