Obographs

Whats changed
Change for 65 - add PropertyType to PROPERTY Nodes
Change for 90 - ensure all declared nodes (CLASS, INDIVIDUAL, PROPERTY) are added even if unlabelled.
Change for 93 - log untranslated axioms to WARN
Change for 103 - remove Guava dependency from obographs-core. Guava is still a transitive dependency of the OWLAPI.
Update examples/ with changes
Update schema/ with changes
Enable obographs-cli to convert ttl to json and yaml

**Full Changelog**: https://github.com/geneontology/obographs/compare/v0.3.0...v0.3.1

This release is a major release which uses the [immutables](immutables.org) library to build the model as immutable objects with corresponding builders. These are (de)serialisable to and from their JSON or YAML representation. The output from these should also be reproducible, predictable and consistent with the ordering in the original OWL file.

This release also splits the library into two modules:
- *obographs-core* contains the model and classes for reading/writing JSON or YAML. Unless you need OWL this is all you need.
- *obographs-owl-api* for reading and converting OWL/OBO into obographs.

*n.b.* the maven coordinates have changed. For example using the core only you will need to add:

xml
<dependency>
<groupId>org.geneontology.obographs</groupId>
<artifactId>obographs-core</artifactId>
<version>0.3.0</version>
</dependency>

Changes: https://github.com/geneontology/obographs/compare/v0.2.0...v0.2.1

Changes: https://github.com/geneontology/obographs/compare/v0.1.0...v0.2.0

* Now handles anonymous individuals in annotations

- 17 - mapped owl:deprecated (obsolete terms)
- 19 - mapped rdfs:comment