Purge inactive doc admins

I'd like to run a DB query to remove the doc admin role from folks that have not made any edits to the handbooks in the last year. David Strauss did this for me last year but I don't think we have an issue with the query (/me smacks her own hand). There is a query in this issue, #287909: Stats query request, that shows who was active within the last year so we just need to futz with it a bit to get a reverse and remove the role.