restrict namespace Geometry to masking.

Core/Binning/Bin.cpp

Core/Binning/SimulationElement.cpp

Core/DecoratedFormFactor/FormFactorDecoratorRotation.h

Core/Export/ExportToPython.cpp

Core/Instrument/Beam.cpp

Core/Instrument/SphericalDetector.cpp

Core/Lattice/Lattice.cpp

Core/Lattice/Lattice.h

Core/Material/HomogeneousMagneticMaterial.cpp

Core/Material/HomogeneousMagneticMaterial.h

Core/Material/HomogeneousMaterial.h

Core/Material/IMaterial.h

Core/Particle/IParticle.cpp

Core/Scattering/Rotations.cpp

Core/Scattering/Rotations.h

Core/Simulation/SpecularSimulation.cpp

Core/Vector/BasicVector3D.cpp

Core/Vector/BasicVector3D.h

Core/Vector/Transform3D.cpp

Core/Vector/Transform3D.h