INSTRUMENT: remember if collapsed

GUI/Model/Descriptor/AxisProperty.cpp

GUI/Model/Descriptor/AxisProperty.h

GUI/Model/Device/BeamDistributionItem.cpp

GUI/Model/Device/BeamDistributionItem.h

GUI/Model/Device/BeamItems.cpp

GUI/Model/Device/BeamItems.h

GUI/Model/Device/DetectorItems.cpp

GUI/Model/Device/DetectorItems.h

GUI/Model/Device/InstrumentItems.cpp

GUI/Model/Device/InstrumentItems.h

GUI/Model/Device/RectangularDetectorItem.cpp

GUI/Model/Device/RectangularDetectorItem.h

GUI/View/Instrument/AxisPropertyEditor.cpp

GUI/View/Instrument/DepthprobeInstrumentEditor.cpp

GUI/View/Instrument/DetectorEditor.cpp

GUI/View/Instrument/DistributionEditor.cpp

GUI/View/Instrument/EnvironmentEditor.cpp

GUI/View/Instrument/FootprintCorrectionEditor.cpp

GUI/View/Instrument/GISASBeamEditor.cpp

GUI/View/Instrument/InclinationAnglesEditor.cpp