Feature/revision istl solvers
I revised the ISTL Solvers in a way that allows to use them inside the implicit RungeKutta solvers. Along with that there is some code cleaning.
@marco.agnese : Please take a look. @tobias.malkmus: Please take a look.
I revised the ISTL Solvers in a way that allows to use them inside the implicit RungeKutta solvers. Along with that there is some code cleaning.
@marco.agnese : Please take a look. @tobias.malkmus: Please take a look.