Use term uncertain

[peterdesmet]

In the controlled vocabularies for establishmentMeans and origin, you currently have:

Origin Uncertain
Presence Uncertain

I would change both to uncertain.

[peterdesmet]

Do you agree or not? This hasn't been changed in the vocabs yet.

Pro tip: if in your commit message you write "Fixes #4" and merge to master, this issue will close automatically, with a reference to the commit.

[qgroom]

Then I must be looking in the wrong place

[as6699]

I balked at "origin uncertain" as well (see my separate pull request). But this is as adopted by IUCN, so there is something to be said for being consistent with their vocabulary.