Add forEachChild(), rename functions to forEach{Snapshot, Instance}

source/RobotAPI/libraries/armem/core/base/CoreSegmentBase.h

source/RobotAPI/libraries/armem/core/base/EntityBase.h

...e/RobotAPI/libraries/armem/core/base/EntitySnapshotBase.h

source/RobotAPI/libraries/armem/core/base/MemoryBase.h

.../RobotAPI/libraries/armem/core/base/ProviderSegmentBase.h

...PI/libraries/armem/core/base/detail/MemoryContainerBase.h

...otAPI/libraries/armem/core/base/detail/iteration_mixins.h

source/RobotAPI/libraries/armem/core/diskmemory/Entity.cpp

...botAPI/libraries/armem/core/diskmemory/EntitySnapshot.cpp

...e/RobotAPI/libraries/armem/core/longtermmemory/Entity.cpp

...PI/libraries/armem/core/longtermmemory/EntitySnapshot.cpp

...PI/libraries/armem/core/workingmemory/ice_conversions.cpp

...PI/libraries/armem/core/workingmemory/visitor/Visitor.cpp

source/RobotAPI/libraries/armem/server/MemoryRemoteGui.cpp

...s/armem/server/query_proc/base/EntityQueryProcessorBase.h

.../server/query_proc/workingmemory/EntityQueryProcessor.cpp

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