Create residual viscosity package +rv and generalize the ResidualViscosity class - Generalize residual viscosity, by passing user-defined flux and calculating the time derivative outside of the update. - Create separate RungekuttaRV specifically using interior RV updates - Separate the artifical dissipation operator from the scheme AdvectionRV1D so that the same scheme can be reused for creating the diff op used by the ResidualViscosity class

% Calcualtes the largest timestep smaller than k_max that gives an integer
% number of timesteps to time T.
%   k_max -- largest allowable timestep
%   T     -- time to align with
%
% Returns:
%   k -- calculated timestep
%   N -- number to of timestep to reach T
function [k, N] = alignedTimestep(k_max, T)
    N = ceil(T/k_max);
    k = T/N;
end