Hi all!

For weeks and months now, we have been discussion how to best represent "extra" information in (or associated with) the wikibase data model. After some more discussion and a bit of research, I think I have found what we need: The Role Object Pattern aka Role Class Model, see https://en.wikipedia.org/wiki/Role_Class_Model.

Please have a look at https://phabricator.wikimedia.org/T118860 and let me know if you have any objections. If not, let's use this sprint to discuss the details of the implementations, and do a task breakdown.

PS: I came across quite a few famous names when during my research. Looks like we are not first in having this need...