Main module headers are moved 1 level up

e.g. <opencv2/core/core.hpp> become <opencv2/core.hpp>

Also renamed <opencv2/core/opengl_interop.hpp> to <opencv2/core/opengl.hpp>

modules/video/perf/perf_precomp.hpp

@@ -9,10 +9,10 @@
 #ifndef __OPENCV_VIDEO_PRECOMP_HPP__
 #define __OPENCV_VIDEO_PRECOMP_HPP__
 
-#include <opencv2/imgproc/imgproc.hpp>
-#include <opencv2/video/video.hpp>
-#include <opencv2/highgui/highgui.hpp>
-#include "opencv2/ts/ts.hpp"
+#include <opencv2/imgproc.hpp>
+#include <opencv2/video.hpp>
+#include <opencv2/highgui.hpp>
+#include "opencv2/ts.hpp"
 
 #ifdef GTEST_CREATE_SHARED_LIBRARY
 #error no modules except ts should have GTEST_CREATE_SHARED_LIBRARY defined