o Major features (relay):
    - Relays no longer run as exits by default. If the "ExitRelay" option is
      auto (or unset), and no exit policy is specified with ExitPolicy or
      ReducedExitPolicy, we now treat ExitRelay as 0. Previously in this
      case, we allowed exit
      traffic and logged a warning message. Closes ticket
      21530. Patch by Neel Chauhan.