Add some missing C++ headers in mapper_cpp.h.
Add some missing C++ headers in mapper_cpp.h.

malloch/libmapper,radarsat1/libmapper,radarsat1/libmapper,radarsat1/libmapper,libmapper/libmapper,libmapper/libmapper,malloch/libmapper,malloch/libmapper,libmapper/libmapper,johnty/libmapper,libmapper/libmapper,malloch/libmapper,malloch/libmapper,malloch/libmapper,johnty/libmapper,johnty/libmapper,radarsat1/libmapper,johnty/libmapper,libmapper/libmapper,libmapper/libmapper,johnty/libmapper,radarsat1/libmapper