Extract imgcodecs module from highgui

samples/cpp/tutorial_code/core/discrete_fourier_transform/discrete_fourier_transform.cpp

@@ -1,5 +1,6 @@
 #include "opencv2/core/core.hpp"
 #include "opencv2/imgproc/imgproc.hpp"
+#include "opencv2/imgcodecs.hpp"
 #include "opencv2/highgui/highgui.hpp"
 
 #include <iostream>

samples/cpp/tutorial_code/core/how_to_scan_images/how_to_scan_images.cpp

@@ -1,5 +1,6 @@
 #include <opencv2/core.hpp>
 #include <opencv2/core/utility.hpp>
+#include "opencv2/imgcodecs.hpp"
 #include <opencv2/highgui.hpp>
 #include <iostream>
 #include <sstream>

samples/cpp/tutorial_code/core/interoperability_with_OpenCV_1/interoperability_with_OpenCV_1.cpp

@@ -3,6 +3,7 @@
 
 #include <opencv2/core/core.hpp>
 #include <opencv2/imgproc/imgproc.hpp>
+#include "opencv2/imgcodecs.hpp"
 #include <opencv2/highgui/highgui.hpp>
 #include <opencv2/core/utility.hpp>
 
@@ -24,6 +25,7 @@ static void help( char* progName)
 
 #ifdef DEMO_MIXED_API_USE
 #  include <opencv2/highgui/highgui_c.h>
+#  include <opencv2/imgcodecs/imgcodecs_c.h>
 #endif
 
 int main( int argc, char** argv )

samples/cpp/tutorial_code/core/mat_mask_operations/mat_mask_operations.cpp

@@ -1,5 +1,6 @@
 #include <opencv2/core.hpp>
 #include <opencv2/core/utility.hpp>
+#include <opencv2/imgcodecs.hpp>
 #include <opencv2/highgui.hpp>
 #include <opencv2/imgproc.hpp>
 #include <iostream>