Check existing fallback fingerprints, IPs, and ports before 0.2.8-rc

I want to run the standard checks on the 100 fallback directories from April 2016 before we put them in a June? 2016 release candidate.

I bet at least one has changed its fingerprint, IP, or ports, and will need to be removed.

I wonder if we should regenerate the list at that point, or just remove (or update) the broken fallbacks?

I'll decide at the time based on how many are broken.