split MaskItems in 3 src pairs

GUI/Model/Data/MaskResultsPresenter.cpp

GUI/Model/Data/ProjectionItems.h

GUI/Model/Detector/DetectorItem.h

GUI/Model/Mask/MaskContainerItem.cpp

GUI/Model/Mask/MaskContainerItem.h

GUI/Model/Mask/MaskContainerModel.cpp

GUI/Model/Mask/MaskContainerModel.h

GUI/Model/Mask/MaskItems.cpp

GUI/Model/Mask/MaskItems.h

GUI/View/Import/RealDataMaskWidget.cpp

GUI/View/Mask/MaskEditorActions.cpp

GUI/View/Mask/MaskEditorCanvas.cpp

GUI/View/Mask/MaskEditorPropertyPanel.cpp

GUI/View/Mask/MaskGraphicsScene.cpp

GUI/View/Projection/ProjectionsEditorActions.cpp