message: Remove redundant precomp.hpp and using-namespace
  Removed redundant precompiled header include
diff: #if !defined CUDA_DISABLER
  -#include "precomp.hpp"
  -
  -using namespace cv;
  -using namespace cv::cuda;
  -
  #include "opencv2/core/cuda/common.hpp"
  #include "opencv2/core/cuda/vec_traits.hpp"
  #include "opencv2/core/cuda/vec_math.hpp"
  