* Altered the algorithm by which the doubly-linked session list is

* Altered the algorithm by which the doubly-linked session list is
  amended and culled.  Decided that performance is better than cute
  session numbers (which we don't display to the users anymore anyway)
  and we now assign a session number (CC->cs_pid) starting with 1 when the
  server starts and incrementing indefinitely.  Need to test this more.