o Major bugfixes (relays, key management):
    - Regenerate link and authentication certificates whenever the key that
      signs them changes; also, regenerate link certificates whenever the
      signed key changes. Previously, these processes were only weakly
      coupled, and we relays could (for minutes to hours) wind up with an
      inconsistent set of keys and certificates, which other relays
      would not accept. Fixes two cases of bug 22460; bugfix on
      0.3.0.1-alpha.