Oxford HUMSOC

Here's an attempt to create what Oxford calls its OXFORD HUMSOC style.  It's used by a number of journals, including Research Evaluation, Science and Public Policy and Migration Studies (although it's possible there are subtle differences in how the journals implement this, a quick check shows quite some variance even between articles in the same issue of a journal!).  It's mentioned on the Zotero forums.  The 'documentation' given to authors is here:  http://www.oxfordjournals.org/our_journals/rev/for_authors/manuscript_instructions.html#Journal%20copyediting%20style  (it's a link to a PDF but this page seems a better link for documentation).

I started with APA 5th edition and worked from there.  Hopefully the commits in the branch that this pull request is coming from explain the changes.  I've tried to meet all the requirements (including validation this time!)

I'd like a dependent style for Research Evaluation journal, but wasn't sure how creating them worked (is it manual or is the utility the way to go?)