HV-878 Integrating Optional and JavaFX types

Do you mean the case where the property type is specified via a type variable, e.g. `ReadOnlyProperty<Foo>`?

If so, you actually can determine the type, `Foo` in this case, as this information is retained in the byte code. We usually work with ClassMate to retrieve the type information, see [here](https://github.com/hibernate/hibernate-validator/blob/master/engine/src/test/java/org/hibernate/validator/test/internal/engine/valuehandling/model/PropertyValueUnwrapper.java) for an example. There is `TypeResolutionHelper` which keeps a single instance of the type resolver, we probably should work with this helper here, too.