Update Bruss for a new release of DiffEqOperators.jl

[YingboMa]

The API of DerivativeOperator has been changed.

https://github.com/JuliaDiffEq/DiffEqProblemLibrary.jl/blob/master/src/ode/brusselator_prob.jl#L100-L107

[kanav99]

Should we make a constructor of DerivativeOperator instead that acts as compatibility for such cases? We don't even have this stuff documented and this kind of change is scary.

[ChrisRackauckas]

should it even use the DerivativeOperator?

[kanav99]

I just replaced

DerivativeOperator{Float64}(2,2,1/(N_brusselator_1d-1),
                                      N_brusselator_1d,
                                      :Dirichlet,:Dirichlet;
                                      BC=(1.,1.))

with

CenteredDifference{Float64}(2,2,1/(N_brusselator_1d-1),N_brusselator_1d)

and it worked for OrdinaryDiffEq tests. Is it right?

[ChrisRackauckas]

yes that's good. PR.

[ChrisRackauckas]

Still not completely fixed since I forgot it needs BCs as well