[hybrid] Allow dune-istl MultiBlock types as ranges in forEach
Currently MultiTypeBlockMatrix can be used as a range in forEach
using namespace Dune::Hybrid;
forEach(m, [](auto& row){
...
});
because it has a static constexpr member function size
. However, size
is deprecated in favour of N
.
This MR attempt at removing the deprecation warning (because N
is looked for first) and also allow types that use a static constexpr member function N
to be interpreted as range
in the sense of Hybrid::forEach
.