Merge branch 'armem/clean-up-interfaces' of https://gitlab.com/ArmarX/RobotAPI into armem/clean-up-interfaces

# Conflicts:
#	source/RobotAPI/libraries/armem/CMakeLists.txt

# Conflicts:
#	source/RobotAPI/libraries/armem/core/longtermmemory/Memory.h
#	source/RobotAPI/libraries/armem/core/workingmemory/Memory.cpp
#	source/RobotAPI/libraries/armem/core/workingmemory/Memory.h
#	source/RobotAPI/libraries/armem_gui/MemoryViewer.cpp

Turn getSnapshots*() into forEach*(), move snapshot query implementations into Entity, fix deprecation warnings