How should qunatity.Domain/find look for domains?
quantity.Domain/find can be called with a quantity.Domain object to look for. Right now, it compares the quantity.Domain only by names and not by the grid data.
pro: same behavior of the method if it is called with a name or a domain to look for. contra: if the method should find a domain, one can expect to get the same domain not only a domain with the same name...
workaround: make the method only callable with names and not with quantity.Domain objects as arguments.