Merged PR 4559: use .hpp instead of .h for C++ for the sake of parsers

use .hpp instead of .h for C++ headers, so parsers operating on them independently (Like CPPToJSON via clang) know they are C++, not C.

Libraries/C++/DataPipelines/v1.0/DataPipelines/SampleTransforms/arithmetic.cpp

@@ -4,7 +4,7 @@
 // ----------------------------------------------------------------------
 
 #include <stdint.h>
-#include "arithmetic.h"
+#include "arithmetic.hpp"
 
 /* Defined in enclosed namespace */
 namespace DataPipelines {