[j.1] merge Dirs into AppConfig; split off WidgetSettings ()

App/main.cpp

GUI/Support/Util/Path.cpp

GUI/Support/Util/Path.h

GUI/View/Canvas/SavePlotAssistant.cpp

GUI/View/Layout/AppConfig.cpp

GUI/View/Layout/AppConfig.h

GUI/View/Loader/ComponentRW.cpp

GUI/View/Loader/DataLoader.cpp

GUI/View/Loader/ProjectionsSaver.cpp

GUI/View/Loader/PythonScriptWidget.cpp

GUI/View/Main/ActionManager.cpp

GUI/View/Main/MainWindow.cpp

GUI/View/Main/MainWindow.h

GUI/View/Manager/NewProjectDialog.cpp

GUI/View/Manager/ProjectManager.cpp

GUI/View/Manager/ProjectManager.h

GUI/View/Manager/PyImportAssistant.cpp

GUI/View/Material/MaterialEditorDialog.cpp

GUI/View/Realspace/RealspaceWidget.cpp

GUI/View/Sample/SampleForm.cpp