Draft: Include all queries and add definitions

This will include adding all the defined inverse and other queries from https://www.valueflo.ws/specification/inverses/#agent-also-subclasses-person-organization, and adding definitions for each.

@Connoropolous I pushed just Agent to start with. Please review and let me know if you want anything done differently, while I'm in the graphql.

@pospi if you catch this, your review from the general vf-graphql perspective would be great also. I'm maintaining what is there already in its existing format.