Since I'm just starting out with git-annex, I've had several false starts in getting things setup nicely between three machines. In the course of so doing, I've ended up with several repositories which no longer exist, and which I've marked dead. However, this is making the "git annex status" report a bit ugly, since these repositories no longer exist and can never exist again. Is there a way to truly purge dead repositories from my annex? I'd be fine with a command that must be ran in tandem on all annexes before doing a sync...