Add general Runge-Kutta class - Add a general Runge-Kutta class which time integrates the solution based on coefficients obtained from a Butcher tableau - Add butcher tableau which returns coefficents for the specified Runge-Kutta method - Remove RungKutta4proper, since obsolete

% Get the index of the points p within the tall array of points ps
function [I, ok] = pointIndex(p, ps)
    [ok, I] = ismember(p,  ps, 'rows');
end