Allow restricting maximum number of multigrid levels
Allow restricting maximum number of multigrid levels

ddemidov/amgcl,ddemidov/amgcl,ddemidov/amgcl,dondieselkopf/amgcl,ddemidov/amgcl,dondieselkopf/amgcl,dondieselkopf/amgcl