treat E-centres in the same way

[bansp]

This is just to document the issue: we store GWDG as a non-depositing E-centre, but it does provide (relatively simple) archiving services: https://docs.gwdg.de/doku.php?id=en%3Aservices%3Astorage_services%3Adata_archiving%3Astart

Perhaps the simplest fix is to set it as a deposition centre, but I'd rather have that documented.

[bansp]

It seems that a parallel should be drawn with MPCDF. GWDG is also an E-centre that allows for massive data archival, as opposed to the kind of preservation that stands behind the idea of data deposition in CLARIN.

Keeping the ticket open until the new stuff is live and we can be sure that both centres are treated alike.

[bansp]

FZJ can be added here as well, and the descriptions are not fully identical. It would be great to find a definition of "E-centres", as the first step.