I've added a -p switch to tetris to switch on previewing of the next
shape, the default is off. 

I'll leave the score-handling for someone else:
 - multiplying the score by some factor <1 if previewing is enabled
   is the easies solution here, but I won't be the one to define that
   factor. 
 - A better way would be to include a flag that tells if previewing
   was used in the highscore list, but this would introduce backward
   compatibility problems with old highscore files.


Enjoy,

 - Hubert


P.S.: 	Rank  Score   Name     (points/level)   
	  1*  14910  feyrer      (7455 on 2)      
	(with previewing... without, it was about 1000 lower)

-- 
Hubert Feyrer <hubert.feyrer@rz.uni-regensburg.de>