Taxon checks should not return invalid when taxon is not known

See email on go-discuss:

> I was not able to propagate mitochondrion to some of the fungal sequences and 
here is what the webservices URL tells me:
> GO:5739 is false for Dikarya.
> 
http://toaster.lbl.gov:9999/isClassApplicableForTaxon?format=txt&idstyle=obo&id=
GO:0005739&taxid=NCBITaxon:451864

Original issue reported on code.google.com by cmung...@gmail.com on 29 Jul 2014 at 7:36

linikujp / owltools

Taxon checks should not return invalid when taxon is not known #99