Misc term updates and EOM refactor

[TomConlin]

minor improvements

• swap out ontology terms that don't exist for terms that do
• stop forcing image urls to be literal strings
• reduce the clutter of edge counts when diffing dots for use with random samples

EOM

I found a fossil too!
hp-to-eom-mapping.tsv mapping repo was touched 4 years ago

• https://github.com/obophenotype/human-phenotype-ontology/tree/master/src/mappings

The ingest speaks of "NIF's DISCO crawler" which apparently put things in a postgress database which has remained available... last modified 2016-11-23 15:53:47.914452

• If this is ingest remains a constant, we could perhaps do something less dynamic
• otherwise we may need to look into fetching EOM data differently