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

Conflicts:
	modules/contrib/src/retina.cpp
	modules/core/include/opencv2/core/mat.hpp
	modules/core/src/algorithm.cpp
	modules/core/src/arithm.cpp
	modules/features2d/src/features2d_init.cpp
	modules/gpu/include/opencv2/gpu/gpu.hpp
	modules/gpu/perf/perf_imgproc.cpp
	modules/imgproc/src/generalized_hough.cpp
	modules/ocl/include/opencv2/ocl/ocl.hpp
	modules/video/src/tvl1flow.cpp
	modules/video/src/video_init.cpp

samples/cpp/calibration_artificial.cpp

@@ -46,7 +46,7 @@ private:
     Point3f generateChessBoardCenter(const Mat& camMat, const Size& imgSize) const;
     Mat rvec, tvec;
 };
-};
+}
 
 
 

samples/cpp/kmeans.cpp

@@ -33,10 +33,10 @@ int main( int /*argc*/, char** /*argv*/ )
     {
         int k, clusterCount = rng.uniform(2, MAX_CLUSTERS+1);
         int i, sampleCount = rng.uniform(1, 1001);
-        Mat points(sampleCount, 1, CV_32FC2), labels;
+        Mat points(sampleCount, 2, CV_32F), labels;
 
         clusterCount = MIN(clusterCount, sampleCount);
-        Mat centers(clusterCount, 1, points.type());
+        Mat centers;
 
         /* generate random sample from multigaussian distribution */
         for( k = 0; k < clusterCount; k++ )

samples/cpp/tutorial_code/ImgProc/Threshold.cpp

@@ -14,7 +14,7 @@ using namespace cv;
 /// Global variables
 
 int threshold_value = 0;
-int threshold_type = 3;;
+int threshold_type = 3;
 int const max_value = 255;
 int const max_type = 4;
 int const max_BINARY_value = 255;