Re #19930 Added remaining logic and connections to GDPP

.../inc/MantidQtCustomInterfaces/Reflectometry/ReflWindow.ui

...dWidgets/DataProcessorUI/AbstractDataProcessorTreeModel.h

...idgets/DataProcessorUI/DataProcessorOneLevelTreeManager.h

...tMantidWidgets/DataProcessorUI/DataProcessorTreeManager.h

...idgets/DataProcessorUI/DataProcessorTwoLevelTreeManager.h

...idWidgets/DataProcessorUI/GenericDataProcessorPresenter.h

...essorUI/GenericDataProcessorPresenterGroupReducerWorker.h

...ocessorUI/GenericDataProcessorPresenterRowReducerWorker.h

...Widgets/DataProcessorUI/QDataProcessorOneLevelTreeModel.h

...Widgets/DataProcessorUI/QDataProcessorTwoLevelTreeModel.h

...ts/src/DataProcessorUI/AbstractDataProcessorTreeModel.cpp

.../src/DataProcessorUI/DataProcessorOneLevelTreeManager.cpp

.../src/DataProcessorUI/DataProcessorTwoLevelTreeManager.cpp

...ets/src/DataProcessorUI/GenericDataProcessorPresenter.cpp

...s/src/DataProcessorUI/QDataProcessorOneLevelTreeModel.cpp

...s/src/DataProcessorUI/QDataProcessorTwoLevelTreeModel.cpp