Version 1.1.5.
Finish 1.1.5.

* Fix odd case in fromRdf where rdf:nil is not used in a list, but is a vocabulary item, such as in the RDF vocabulary definition.
* Support :unique_bnodes option to make sure that randomized BNode lables are generated when flattening or writing.
* Minor update for in resource to see if a node is a node ref.