encrypted ID of SequenceFeature not loaded when using IOTools.fromRdfXml()

[nroehner]

I've found that the id field (not displayId) for a SequenceFeature is null when loading a Library from a rdf file using IOTools.fromRdfXml(), even though the feature clearly had such an encrypted ID when it was first created and written to the rdf file using IOTools.toRdfXml().