* [RFC5646,NEW] Added RDF version of IANA language tag registry.
* [RFC5646_DCG,EXT] Added class checks using the RDF version of the IANA registry.
* [RFC5646_IANA,EXT] Added class check predicate.
* [RFC5646_IANA,EXT] Use the new XSD datatypes for RDF assertions.
* [XSD,NEW] Added xsd_lexicalCanonicalMap/3 that rountrips from lexical literal to value to canonical literal.
* [XSD_INTEGER,NEW] Added support for XSD 1.1 integer datatype.