Allow curation workflow to only be required for individual records

[max-moser]

Right now, the curation workflow can only be enabled or disabled globally (i.e. for all new records).
However, it may be interesting for some operators to require the curation workflow only for a certain subset of records or users.

For example:

as an administrator, I want all dissertations and theses to be curated, but I don't want any image submissions to be curated.