REL-2059: Fix faulty comparison of enum options in Obs objects.

This is a fix I need to get some other (unrelated) tests working I was originally working on.. Side effects on QPT should be minimal because options are mainly used for informational purposes (displayed as properties for the selected observation). This is probably also the reason why nobody noticed this.
Is this essentially the same as the both `null` case?  I know you've covered the bases but it's difficult to see how we can be sure that `o1` and `o2` are the same type. I think it's because ORDER is guaranteed not to return the same Integer value for different enums?