ts: refactor OpenCV tests

- removed tr1 usage (dropped in C++17)
- moved includes of vector/map/iostream/limits into ts.hpp
- require opencv_test + anonymous namespace (added compile check)
- fixed norm() usage (must be from cvtest::norm for checks) and other conflict functions
- added missing license headers

modules/imgproc/test/test_grabcut.cpp

@@ -42,11 +42,7 @@
 
 #include "test_precomp.hpp"
 
-#include <string>
-#include <iostream>
-
-using namespace std;
-using namespace cv;
+namespace opencv_test { namespace {
 
 class CV_GrabcutTest : public cvtest::BaseTest
 {
@@ -170,3 +166,5 @@ TEST(Imgproc_GrabCut, repeatability)
     EXPECT_EQ(0, countNonZero(mask_1 != mask_3));
     EXPECT_EQ(0, countNonZero(mask_2 != mask_3));
 }
+
+}} // namespace