Use `unknown` instead of `undetermined` for sex vocabulary

[peterdesmet]

https://rs.gbif.org/vocabulary/gbif/sex.xml has the values:

male (alt: ♂)
female (alt: ♀)
hermaphrodite (alt: Zwitter)
undetermined (alt: unbestimmt)

I recognize that there is a semantic difference between undetermined and unknown, but the unknown is already used in other controlled vocabularies:

• LifeStage: https://registry.gbif.org/vocabulary/LifeStage/concept/Unknown
• EstablishmentMeans, alternative for uncertain: https://registry.gbif.org/vocabulary/EstablishmentMeans/concept/Uncertain
• Sex as defined by Movebank: http://vocab.nerc.ac.uk/collection/MVB/current/MVB000023/

Would it therefor be possible to either:

• Add unknown as the recommended term (cf. LifeStage), with undetermined as alternative
• Or add unknown as alternative label for undetermined

[peterdesmet]

In addition, would it be possible to move this vocabulary to https://registry.gbif.org/vocabulary/search?

[timrobertson100]

In addition, would it be possible to move this vocabulary to https://registry.gbif.org/vocabulary/search?

GBIF is working through all the vocabs now, led by new GBIF member @CecSve. Suggest we pick this up with gbif/vocabulary#83

[peterdesmet]

Great, I notice UNKNOWN is suggested as a concept there. 👍