tor/changes/bug4759

  o Minor bugfixes:

    - Make sure we never mark the wrong rendezvous circuit as having
      had its introduction cell acknowleged by the introduction-point
      relay.  Previously, when we received an INTRODUCE_ACK cell on a
      client-side hidden-service introduction circuit, we might have
      marked a rendezvous circuit other than the one we specified in
      the INTRODUCE1 cell as INTRO_ACKED, which would have produced a
      warning message and interfered with the hidden service
      connection-establishment process.  Bugfix on 0.2.3.3-alpha, when
      the stream-isolation feature which might cause Tor to open
      multiple rendezvous circuits for the same hidden service was
      added.  Fixes bug 4759.