Aggregate no longer knows about Multilayer.

Core/Aggregate/ParticleLayout.cpp

Core/Multilayer/DecouplingApproximationStrategy.cpp

Core/Multilayer/DecouplingApproximationStrategy.h

Core/Multilayer/IInterferenceFunctionStrategy.cpp

Core/Multilayer/IInterferenceFunctionStrategy.h

Core/Multilayer/InterferenceFunctionStrategies.h

Core/Multilayer/LayerSpecularInfo.cpp

Core/Multilayer/LayerSpecularInfo.h

...ultilayer/SizeSpacingCorrelationApproximationStrategy.cpp

.../Multilayer/SizeSpacingCorrelationApproximationStrategy.h

auto/Wrap/doxygen_core.i

auto/Wrap/libBornAgainCore.py

auto/Wrap/libBornAgainCore_wrap.cpp