2006-02-20 jrandom

    * Major SSU and router tuning to reduce contention, memory usage, and GC
      churn.  There are still issues to be worked out, but this should be a
      substantial improvement.
    * Modified the optional netDb harvester task to support choosing whether
      to use (non-anonymous) direct connections or (anonymous) exploratory
      tunnels to do the harvesting.  Harvesting itself is enabled via the
      advanced config "netDb.shouldHarvest=true" (default is false) and the
      connection type can be chosen via "netDb.harvestDirectly=false" (default
      is false).