I'm slightly concerned about the semantics of `isNotEmpty` here as opposed to just `getUserSpecifiedDescription() == null ? null : rstring(...)`.

If a user wants to actively override the description in the OME-XML to have it blank, do they have any way to do that? Would they assume that `--description=""` would do so? Or do we tell them to use `--description=" "` (empty space)? /cc @chris-allan as the original author and frequent user of the feature.