Create customised plugin for CitationJS

[bootsa]

Much of the processing can be done within CitationJS. The current Wikidata CitiationJS plugin doesn't provide all the data we require and has a few oddities (defaulting to type book, for instance).

Creating our own plugin based off of the Wikidata plugin would allow us to draw more data directly and also, potentially, output the XML directly making a cleaner pipeline and allowing better expansion for a full Wikibase to BASE processing pipeline.