[Dune] Periodicity for unstructured grids

[Aleksejs Fomins]

Dear Dune,

I need to implement periodic boundary conditions into dune-curvilineargrid now.

Would you be so kind to tell me if the current dune-grid interface envisions periodic boundaries and associated ghost elements, and how.

The questions of interest are: partiton type, behavior of intersection, behavior of DataHandle

Best regards,
Aleksejs