Fetches custom defined properties on a given document
[{ "id":"integer", "feltNavn":"string", "verdi":"string" }]
Add or update a custom defined property on a given document. If `Overskriv` is true and a property with the same name exists, the value will be updated. Otherwise a new property will be added.
{ "feltNavn":"string", "verdi":"string", "overskriv":"boolean" }
{ "id":"integer", "feltNavn":"string", "verdi":"string" }