split GUI/Model/Group into 10 dirs

GUI/Model/Data/Data1DViewItem.h

GUI/Model/Data/DataItem.h

GUI/Model/Data/IntensityDataItem.h

GUI/Model/Fit/MinimizerItem.h

GUI/Model/G0/DistributionItems.cpp

GUI/Model/G0/DistributionItems.h

GUI/Model/G1/FilterPropertyProxy.cpp

GUI/Model/G1/FilterPropertyProxy.h

GUI/Model/G2/GroupInfo.cpp

GUI/Model/G2/GroupInfo.h

GUI/Model/G3/GroupItem.cpp

GUI/Model/G3/GroupItem.h

GUI/Model/G4/GroupItemController.cpp

GUI/Model/G4/GroupItemController.h

GUI/Model/G5/ItemCatalog.cpp

GUI/Model/G5/ItemCatalog.h

GUI/Model/G6/PropertyItem.cpp

GUI/Model/G6/PropertyItem.h

GUI/Model/G7/ItemFactory.cpp

GUI/Model/G7/ItemFactory.h