add method to curate oligomerization states to wiki documentation

[ValWood]

Document oligomerizatio curation here:
document this here
https://github.com/pombase/curation/wiki/Working-with-contig-files

This is all I can find in
https://docs.google.com/document/d/1M4zca0WRPv0nUOHIIcq2gleQ4ENi0gGnPxvbthSx1HE/edit?tab=t.0#heading=h.mm5ckaol7w0i

Oligomerization states
/controlled_curation="term=subunit composition, homooligomeric; cv=subunit_composition; db_xref=PMID:17208257; date=20080417"
/controlled_curation="term=subunit composition, homomeric(2); cv=subunit_composition; db_xref=PMID:11884628; date=20051017"

(replace the info in the curation catalog with a link to the wiki docs)

[ValWood]

@kimrutherford could you query for all examples of "subunit composition" plus extensions so that we can write new docs.
I think this used to be described on the old wiki, but I can't find it.

cc @PCarme