Log Message:
Update to 0.2.1.20.  From Christian Sturm in PR pkg/42311.

Changes in version 0.2.1.20 - 2009-10-15
  o Major bugfixes:
    - Send circuit or stream sendme cells when our window has decreased
      by 100 cells, not when it has decreased by 101 cells. Bug uncovered
      by Karsten when testing the "reduce circuit window" performance
      patch. Bugfix on the 54th commit on Tor -- from July 2002,
      before the release of Tor 0.0.0. This is the new winner of the
      oldest-bug prize.
    - Fix a remotely triggerable memory leak when a consensus document
      contains more than one signature from the same voter. Bugfix on
      0.2.0.3-alpha.
    - Avoid segfault in rare cases when finishing an introduction circuit
      as a client and finding out that we don't have an introduction key
      for it. Fixes bug 1073.

  o Major features:
    - Tor now reads the "circwindow" parameter out of the consensus,
      and uses that value for its circuit package window rather than the
      default of 1000 cells. Begins the implementation of proposal 168.

  o New directory authorities:
    - Set up urras (run by Jacob Appelbaum) as the seventh v3 directory
      authority.
    - Move moria1 and tonga to alternate IP addresses.

  o Minor bugfixes:
    - Fix a signed/unsigned compile warning in 0.2.1.19.
    - Fix possible segmentation fault on directory authorities. Bugfix on
      0.2.1.14-rc.
    - Fix an extremely rare infinite recursion bug that could occur if
      we tried to log a message after shutting down the log subsystem.
      Found by Matt Edman. Bugfix on 0.2.0.16-alpha.
    - Fix an obscure bug where hidden services on 64-bit big-endian
      systems might mis-read the timestamp in v3 introduce cells, and
      refuse to connect back to the client.  Bugfix on 0.2.1.6-alpha.
    - We were triggering a CLOCK_SKEW controller status event whenever
      we connect via the v2 connection protocol to any relay that has
      a wrong clock. Instead, we should only inform the controller when
      it's a trusted authority that claims our clock is wrong. Bugfix
      on 0.2.0.20-rc; starts to fix bug 1074.
    - We were telling the controller about CHECKING_REACHABILITY and
      REACHABILITY_FAILED status events whenever we launch a testing
      circuit or notice that one has failed. Instead, only tell the
      controller when we want to inform the user of overall success or
      overall failure. Bugfix on 0.1.2.6-alpha. Fixes bug 1075.
    - Don't warn when we're using a circuit that ends with a node
      excluded in ExcludeExitNodes, but the circuit is not used to access
      the outside world. This should help fix bug 1090. Bugfix on
      0.2.1.6-alpha.
    - Work around a small memory leak in some versions of OpenSSL that
      stopped the memory used by the hostname TLS extension from being
      freed.

  o Minor features:
    - Add a "getinfo status/accepted-server-descriptor" controller
      command, which is the recommended way for controllers to learn
      whether our server descriptor has been successfully received by at
      least on directory authority. Un-recommend good-server-descriptor
      getinfo and status events until we have a better design for them.