Transferoperatorassembler does not work with current AluGrid
Currently in dune-alugrid the level of an entity is the level of its creation. In the leafview of a uniformly refined grid, each vertex should have level=maxlevel, which is not the case for Alugrid.
A corresponding fix 4 month ago recently magically disappeared from dune-alugrid/master and until it appears again, the TransferoperatorAssembler
won't behave correctly for Alugrid