Rename module and assocaited classes

MDANSE/Framework/Configurators/AtomSelectionConfigurator.py

.../Framework/Configurators/AtomTransmutationConfigurator.py

MDANSE/Framework/Configurators/AtomsListConfigurator.py

MDANSE/Framework/Configurators/AxisSelectionConfigurator.py

MDANSE/Framework/Configurators/BasisSelectionConfigurator.py

MDANSE/Framework/Configurators/PartialChargeConfigurator.py

MDANSE/Framework/Configurators/QVectorsConfigurator.py

MDANSE/Framework/Plugins/AtomSelectionPlugin.py

MDANSE/Framework/Plugins/AtomsListPlugin.py

MDANSE/Framework/Plugins/PartialChargesPlugin.py

MDANSE/Framework/Plugins/QVectorsPlugin.py

MDANSE/Framework/UserDefinitionStore.py

MDANSE/Framework/Widgets/AtomSelectionWidget.py

MDANSE/Framework/Widgets/AtomTransmutationWidget.py

MDANSE/Framework/Widgets/AtomsListWidget.py

MDANSE/Framework/Widgets/PartialChargesWidget.py

MDANSE/Framework/Widgets/QVectorsWidget.py

MDANSE/Framework/Widgets/UserDefinitionWidget.py

MDANSE/GUI/UserDefinitionViewer.py