armem_robot_mapping: moving all relevant classes / functions into armarx::armem namespace

source/RobotAPI/libraries/armem_robot_mapping/CMakeLists.txt

...otAPI/libraries/armem_robot_mapping/MappingDataReader.cpp

...obotAPI/libraries/armem_robot_mapping/MappingDataReader.h

...obotAPI/libraries/armem_robot_mapping/MappingDataWriter.h

...botAPI/libraries/armem_robot_mapping/aron_conversions.cpp

...RobotAPI/libraries/armem_robot_mapping/aron_conversions.h