watchtower visibility change

Date:Fri Aug 21 12:02:22 2009
As of next reboot, watchtowers will no longer report movement between
rooms that are barely outside of the watched area. Those movements
were never meant to be displayed, but they have been shown up until
now because of a bug.

This change should have no practical affect on game play, but you might
notice the difference if you use watchtowers a lot.