[wip] adding jsonld context

[bollwyvl]

As per #42.

This context is not ready for primetime, but it sort of does the thing.

Currently hardcoded in:

• https://github.com/bollwyvl/resumeToJSONLD
• https://github.com/bollwyvl/registry-server

[olivif]

seems like tests are failing here. I think we also agreed to revisit the schema.org vocabulary post v1 in #42.

[olivif]

Stale PR. Thanks for your contribution @bollwyvl and apologies for the late progress on this.