enhance work lookup function by tracking works current user is using 5pts

[paregorios]

This ticket requests an enhancement to the Pleiades work lookup functionality implemented for #490 by adding the ability to keep track of short titles and URIs of works that this user has fetched from Zotero. Add them to a "combined works" list for the user that is initiated with everything in the "default works" list. Specifically, let's consider an item "used" when it's selected in the form UI, before the "Save" button is clicked and add its short-title to the users' combined works list. Preserve the user's combined works list for the duration of their current session, but start over with an empty list the next time they login.