Move new 2d decay functions of 2d lattice iff to GUI

Core/Algorithms/inc/FTDistributions.h

Core/Algorithms/src/FTDistributions.cpp

Core/PythonAPI/src/FTDistribution2DCauchy.pypp.cpp

Core/PythonAPI/src/FTDistribution2DCone.pypp.cpp

Core/PythonAPI/src/FTDistribution2DGate.pypp.cpp

Core/PythonAPI/src/FTDistribution2DGauss.pypp.cpp

Core/PythonAPI/src/FTDistribution2DVoigt.pypp.cpp

Core/PythonAPI/src/IFTDistribution2D.pypp.cpp

Core/Samples/src/ParticleLayout.cpp

GUI/coregui/Models/GroupPropertyRegistry.cpp

GUI/coregui/Models/InterferenceFunctionItems.cpp

GUI/coregui/Models/item_constants.h