GUI/View: decouple Item from Common

GUI/View/Fit/FitParameterWidget.h

GUI/View/Fit/ParameterTuningWidget.cpp

GUI/View/Fit/ParameterTuningWidget.h

GUI/View/Fit/RunFitControlWidget.h

GUI/View/Fit/SliderSettingsWidget.h

GUI/View/Import/RealDataMaskWidget.h

GUI/View/Import/RealDataSelectorWidget.cpp

GUI/View/Import/SpecularDataImportWidget.h

GUI/View/Instrument/InstrumentView.cpp

GUI/View/Item/DataAccessWidget.cpp

GUI/View/Item/DataAccessWidget.h

GUI/View/Item/ItemComboToolbar.h

GUI/View/Item/ItemComboWidget.h

GUI/View/Item/StyledToolbar.cpp

GUI/View/Item/StyledToolbar.h

GUI/View/Job/JobListView.cpp

GUI/View/Mask/MaskEditorPropertyPanel.h

GUI/View/MaterialEditor/MaterialEditorDialog.cpp

GUI/View/Plot2D/IntensityDataCanvas.h

GUI/View/Plot2D/IntensityDataWidget.h