rename RealModel -> DatafilesModel

GUI/Model/Model/DatafilesCleaner.h

GUI/Model/Model/DatafilesModel.cpp

GUI/Model/Model/DatafilesModel.h

GUI/Model/Model/DatafilesTree.cpp

GUI/Model/Model/DatafilesTree.h

GUI/Model/Project/LinkInstrumentManager.cpp

GUI/Model/Project/LinkInstrumentManager.h

GUI/Model/Project/ProjectDocument.cpp

GUI/Model/Project/ProjectDocument.h

GUI/View/Project/SimulationView.cpp

Tests/Unit/GUI/TestLinkInstrument.cpp

Tests/Unit/GUI/TestProjectDocument.cpp

Tests/Unit/GUI/TestRealModel.cpp

Tests/Unit/GUI/Utils.cpp

Tests/Unit/GUI/Utils.h