RDF version of Content Dictionaries

[kenwenzel]

I can provide an RDF version of the content dictionaries. Currently the repository is hosted at:
https://github.com/numerateweb/openmath-cd

The corresponding schema files (ontologies) can be found at:
https://github.com/numerateweb/numerateweb/tree/master/bundles/core/org.numerateweb.math/src/main/resources/META-INF/ontologies

The RDF version can directly be loaded into any RDF-compatible graph store (RDF4J, Jena, Blazegraph, GraphDB, Allegrograph, Stardog and others).

If there is any interest then it is also possible to set up a Travis job for automatically converting the content dictionaries from this repository after a change.