Include obsolete taxa

[jamesaoverton]

As far as I can tell, we have never included obsolete taxa in our ncbitaxon.owl. (There's nothing obvious in the old code, and grep owl:deprecated ncbitaxon.owl returns nothing.)

taxdmp.zip includes tax_ids for merged and deleted nodes (merged.dmp and delnodes.dmp), but no other information. This is enough to add obsolete classes like this:

NCBITaxon:12 a owl:Class
; rdfs:label "obsolete taxon 12"^^xsd:string
; owl:deprecated "true"^^xsd:boolean
; IAO:0100001 NCBITaxon:74109 # term replaced by
.

NCBITaxon:2663962 a owl:Class
; rdfs:label "obsolete taxon 2663962"^^xsd:string
; owl:deprecated "true"^^xsd:boolean
.