Refactoring: amended getters' names to comply with CSG

Core/Export/ExportToPython.cpp

Core/Fitting/FitObject.cpp

Core/Instrument/IDetector.cpp

Core/Instrument/IDetector.h

Core/Instrument/IDetector2D.cpp

Core/Instrument/IDetector2D.h

Core/Instrument/Instrument.cpp

Core/Instrument/IsGISAXSDetector.cpp

Core/Instrument/RectangularDetector.cpp

Core/Instrument/RectangularDetector.h

Core/Instrument/SimulationArea.cpp

Core/Instrument/SphericalDetector.cpp

Core/Instrument/SphericalDetector.h

GUI/coregui/Models/JobItemUtils.cpp

GUI/coregui/Models/TransformFromDomain.cpp

Tests/UnitTests/Core/Detector/SimulationAreaTest.h

Tests/UnitTests/Core/Detector/SphericalDetectorTest.h