o Major bugfixes (security, relay):
    - When running as a relay, make sure that we never build a path through
      ourselves, even in the case where we have somehow lost the version of
      our descriptor appearing in the consensus. Fixes part of bug 21534;
      bugfix on 0.2.0.1-alpha. This issue is also tracked as TROVE-2017-012
      and CVE-2017-8822.