* Removed the concept of "no bandwidth limit" - if none is specified, its
      16KBps in/out.
    * Include ack packets in the per-peer cwin throttle (they were part of the
      bandwidth limit though).
    * Tweak the SSU cwin operation to get more accurrate estimates under
      congestions.
    * SSU improvements to resend more efficiently.
    * Added a basic scheduler to eepget to fetch multiple files sequentially.