* [DCG_YEAR,SC] Added year//2 to the public predicates.
* [RDF_STATISTICS,NEW] Added rdf_property_table/3 which returns a nested lists representing the rows of a table describing the statistics of the given RDF property.
* [DCG_GENERIC,FIX] The intentions behind the implementation of dcg_peek_length/2 were unclear to me. Rewrote it with less ambition.