partial vector<> support in Java API generator

modules/java/src/cpp/utils.cpp

@@ -0,0 +1,3 @@
+#include "utils.h"
+
+using namespace cv;

modules/java/src/cpp/utils.h

@@ -0,0 +1,3 @@
+#include <jni.h>
+
+#include "opencv2/core/core.hpp"