[pbmserv] Broadcast from camb via PBM Server

[pbmserv <pbmserv@gamerz.net>]

Some improvements have been made to Yacht.

1) The scorecard is now slightly more compact.

2) Resignation handling has been fixed. Players should now feel free to 
bail at the slightest whiff of trouble.

3) An option -hide has been added which hides rerolls from opponents. This 
dramatically reduces the number of mails generated per game, and means that 
player messages are not repeated to opponents multiple times throughout 
each turn. However it also means that opponents will only see the dice 
rolled at the start of each opponent's turn, which are not necessarily the 
dice used for scoring.