rnd-20040612-4-src

rnd-20040612-4-src
* fixed blocking delay of last field for EM and SP style block delay
* fixed bug where the player had to wait for the usual move delay after
  unsuccessfully trying to move, when he directly could move after that
* the last two changes should make original Supaplex level 93 solvable
* improved use of random number generator to make it less predictable