Extend the number of elements that are being displayed to be more appropriate for...

Extend the number of elements that are being displayed to be more appropriate for academic institutions.
Hide elements that contain no content.
Display URLs in a way that makes sense for our legacy practice (all link text went into subfield z instead of y),
although it should still be usable by institutions that do things the right way :)
Try to fix unAPI now that Zotero is parsing the post-JS DOM (having two unAPI entries for a single record is not good).

git-svn-id: svn://svn.open-ils.org/ILS-Contrib/conifer/trunk@599 6d9bc8c9-1ec2-4278-b937-99fde70a366f