Draft implementation of RungeKutta with exterior RV updates - Draft class RungeKuttaExteriorRV which updates the residual using a BDF approximation of the derivtive outside of the RK stages. - Draft class for BDF derivative

function saveFigurePosition()
    defaultPosition = get(0,'defaultfigureposition');
    f = gcf;
    defaultPosition(1:2) = f.Position(1:2);
    set(0,'defaultfigureposition',defaultPosition);
end