[Dune] Scalability of parallel grid construction

[Christian Engwer]

Hi Markus,

> I  do not think that this is an answer to Aleksejs question. I sounded
> to as if he was asking how to setup the communication interfaces
> within the grid implementation in a scalable manner.

then I'm even more puzzled, as he has full access to the internals, it
should be information which is immediatelly available.

@Aleksejs could you shed some more light on this question?

Christian