remove ObservableArray.isReferenceType, update state object methods to support parameterType serialization. Add support for this in FAMB and convert ItemIO->ReferenceIO, https://github.com/phetsims/phet-io/issues/1409
remove ObservableArray.isReferenceType, update state object methods to support parameterType serialization. Add support for this in FAMB and convert ItemIO->ReferenceIO, https://github.com/phetsims/phet-io/issues/1409

phetsims/tandem,phetsims/tandem,phetsims/tandem