  o Minor bugfixes (TLS protocol, integration tests):
    - When classifying a client's selection of TLS ciphers, if the client
      ciphers are not yet available, do not cache the result. Previously,
      we had cached the unavailability of the cipher list and never looked
      again, which in turn led us to assume that the client only supported
      the ancient V1 link protocol.  This, in turn, was causing Stem
      integration tests to stall in some cases.
      Fixes bug 30021; bugfix on 0.2.4.8-alpha.
