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

samples/cpp/tutorial_code/TrackingMotion/cornerDetector_Demo.cpp

@@ -120,4 +120,3 @@ void myHarris_function( int, void* )
      }
   imshow( myHarris_window, myHarris_copy );
 }
-

samples/cpp/tutorial_code/TrackingMotion/cornerSubPix_Demo.cpp

@@ -102,4 +102,3 @@ void goodFeaturesToTrack_Demo( int, void* )
   for( size_t i = 0; i < corners.size(); i++ )
      { cout<<" -- Refined Corner ["<<i<<"]  ("<<corners[i].x<<","<<corners[i].y<<")"<<endl; }
 }
-

samples/cpp/tutorial_code/TrackingMotion/goodFeaturesToTrack_Demo.cpp

@@ -90,4 +90,3 @@ void goodFeaturesToTrack_Demo( int, void* )
   namedWindow( source_window, WINDOW_AUTOSIZE );
   imshow( source_window, copy );
 }
-