peers that we would crawl the entire netDb looking for (always failing, since there aren't any current
netDb entries for that peer that we would accept).
* keep a shitlist of keys we have recently searched for but were unable to find so we don't flood
* if our in-memory data store won't accept the data, its not helpful, so delete it on disk
* no need to do the preemptive refetching of a leaseSet, since we already garlic wrap it with payloads
* logging