Update oUF to newer version
ElvUI uses a modified version of oUF -- i.e, as per comments like this:
-- updating of "invalid" units, function edited by ElvUI
... which means that it's not as simple as swapping out ElvUI's library copy of oUF for a newer version. The updated version of oUF has a few useful tweaks, and it would be nice if ElvUI's oUF were updated to match the current release.