Controlled lists for metadata key-pair values

[hrzepa]

We are using for inchi metadata, which is controlling the namespace for InChI.

However the edit interface on the repository allows uncontrolled key/value pairs, and presumably the metadata sent to DataCite has no scheme URI specified.

1. Should a third field be added to the edit interface to add a scheme IRI if one is desired?

2. But how should the subjectscheme name and URI be controlled?

3. Should eg the values for be controlled by Symplectic, in the same way that grant values are controlled?

I think this has to be the next top priority development for the repository.