Merge remote-tracking branch 'upstream/3.4' into merge-3.4

diff --cc CMakeLists.txt
Simple merge

diff --cc modules/core/include/opencv2/core/utils/tls.hpp
Simple merge

diff --cc modules/python/src2/cv2.cpp
index 1e7bfd6,8272513..abe7253
--- 1/modules/python/src2/cv2.cpp
--- 2/modules/python/src2/cv2.cpp
+++ b/modules/python/src2/cv2.cpp
@@@ -29,9 -29,10 +29,11 @@@
  
  #define MODULESTR "cv2"
  #define NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION
 +
  #include <numpy/ndarrayobject.h>
  
+ #include "opencv2/opencv_modules.hpp"
+ #include "opencv2/core.hpp"
  #include "opencv2/core/utils/configuration.private.hpp"
  #include "opencv2/core/utils/logger.hpp"
  #include "opencv2/core/utils/tls.hpp"