Add describe and update predicates #359
Description
We (mis)use the SHACL specified properties to structurally encode SPARQL examples.
So we have a lot of triples with this as a predicate
It would be nice if the other SPARQL (update) types of queries would also be included.
The graph maintenance options would be interesting for rules even they may not be use able in a validation environment.
We have defined our own predicate for the describe queries, which are understandably not in SHACL 1, but it would be a trivial addition.