Include other graph projection patterns

[cmungall]

In the OAK docs we describe some graph projection patterns implemented by different backends:

https://incatools.github.io/ontology-access-kit/guide/relationships-and-graphs.html#further-notes-on-owl-and-graph-projection

Many users of OAK want to be able to do things like navigate from "Illumina" to find things "manufactured by" Illumina. This is represented by HasValue restrictions. This is pattern is less common for the ontologies that are currently populated in Ubergraph, but if RG is to be used more widely then we need. A wider set is also provided by OBASK.

See:

• Expand documentation on graph projections and allow finer grained control ontology-access-kit#809

The top level of the docs for RG say this is a tool for materializing existentials, so perhaps it is fine to focus on this. HasValue is outside the scope of what is supported in EL anyway (though it would be easy to have incomplete rules). But it would be good to link to some documentation that states this more explicitly.

See also

• Include ObjectPropertyAssertion axioms as triples #152
• include RBox #195
• lightweight adoption of owlstar graph-level annotations #114