Make getters return references instead of pointers

source/RobotAPI/libraries/armem/component/IceMemory.cpp

...otAPI/libraries/armem/component/MemoryComponentPlugin.cpp

source/RobotAPI/libraries/armem/memory/CoreSegment.cpp

source/RobotAPI/libraries/armem/memory/CoreSegment.h

source/RobotAPI/libraries/armem/memory/Entity.cpp

source/RobotAPI/libraries/armem/memory/Entity.h

source/RobotAPI/libraries/armem/memory/EntitySnapshot.cpp

source/RobotAPI/libraries/armem/memory/EntitySnapshot.h

source/RobotAPI/libraries/armem/memory/EntityStorage.cpp

source/RobotAPI/libraries/armem/memory/EntityStorage.h

source/RobotAPI/libraries/armem/memory/Memory.cpp

source/RobotAPI/libraries/armem/memory/Memory.h

source/RobotAPI/libraries/armem/memory/ProviderSegment.cpp

source/RobotAPI/libraries/armem/memory/ProviderSegment.h

source/RobotAPI/libraries/armem/test/ArmemMemoryTest.cpp