New vocabularies
* RDF::Vocab::Bibframe - [Bibliographic Framework Initiative](http://bibframe.org/vocab/) (LoC)
* RDF::Vocab::DataCite - [DataCite Ontology](http://purl.org/spar/datacite/)
* RDF::Vocab::DWC - [Darwin Core](http://rs.tdwg.org/dwc/terms/)
New rake tasks
`rake vocabs:list` - List all included vocabularies