Request: new field for synonym permutations

[matentzn]

We have been implementing a feature to allow synonym permutation support in dosdp tools - controlled by a command line parameter. So when someone says: "permutate" ALL textual features are permutated against exact synonyms. That, of course, is not ideal (think of definitions). So what I want to propose is a new flag "permutate-synonyms" that can take values corresponding to synonym type fields (a list). Usually, that would be "exact synonyms", but to keep it flexible it's probably good to allow arbitrary properties like alternative term from IAO, skos preferred label etc. I don't know if we should use the property fields for this or just add property iris.