Discuss: add import for REX

[cmungall]

http://obofoundry.org/ontology/rex

this has concepts for processes like nuclear fission that may be useful

note although the site doesn't show it, rex is orphaned - https://github.com/OBOFoundry/OBOFoundry.github.io/issues/788

on the one hand I don't like a dependency on an ontology with no owner

on the other hand the quality seems fine, and the content is likely stable

one option would be to adopt rex

[pbuttigieg]

Xref https://github.com/OBOFoundry/OBOFoundry.github.io/issues/2002