Orphaned URIs

[crstn]

How do we handle orphaned URIs? W.r.t. the vocab, this especially refers to properties or classes that we have removed from the standard at some point.

One idea would be to write a clean-up script that goes through all triples in the store on a regular basis and removes all of those which use a property or class that is not in the standard any more.

[crstn]

A "cleaner" way to handle this is probably to stop removing things at some point, and only mark them as deprecated in the standard. This makes it more transparent, because we can also explain in the deprecation note why this class/property should not be used anymore. Plus existing triples don't "break".