pulled alex changes
Disabled Nagle's algorithm.  This cut the mouse response-latency way down.
Brought Alexs physics part back in.  Looks a lot like a working setup.  Two clients can run on the same machine - active window gets the mouse movements.  Next step if we continue might be to make the physics and display dependent on the parameters in GameBoard, rather than hard-coding the window to be 1000 x 1000 pixels.
commit before pulling Greg
resolved conflicts
final commit