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/cudaoptflow/test/test_optflow.cpp

@@ -44,9 +44,7 @@
 
 #ifdef HAVE_CUDA
 
-using namespace cvtest;
-
-namespace {
+namespace opencv_test { namespace {
 
 //////////////////////////////////////////////////////
 // BroxOpticalFlow
@@ -403,6 +401,6 @@ INSTANTIATE_TEST_CASE_P(CUDA_OptFlow, OpticalFlowDual_TVL1, testing::Combine(
     ALL_DEVICES,
     testing::Values(Gamma(0.0), Gamma(1.0))));
 
-} // namespace
 
+}} // namespace
 #endif // HAVE_CUDA