Improve phyloreference representation

[gaurav]

Based on feedback from today's meeting:

• [x] Rewrite phyloreferences to match a single node (the "pinning" node) instead of that node and all its descendants -- this should make testing much easier!
• [x] Each phyloreference should include a Protege-compatible version (i.e. using "has_Descendant" instead of obo:CDAO_0000174).
  • Since Protege is open-source, perhaps the code it uses to do this is available somewhere?
  • Actually, since one of our goals is a web service to carry out phyloreferences, we might be able to create a simple website that allows you to run phyloreferences against any phylogeny already uploaded to our test suite. This might be an easier way to work on phyloreferences collaboratively than screensharing Protege?
• [ ] Figure out how to visualize RDF as in https://github.com/phylotastic-legacy/ontologies/blob/master/tnrs/tnrs-instance-1otu.png

[gaurav]

The first two are partially implemented in PhyloDeRef now, while the last one would fit there better than it would in phylo2owl, I think. Therefore I'm closing this and moving that last point to PhyloDeRef as https://github.com/gaurav/phyloderef/issues/5