Creater.create uses Random.split to get different renerators for

creating the random solved puzzle and shuffling the layout.  This
porbably doesn't matter here, which is good because the generators
aren't really independent right now, as per the doc and as described
at haskell/random#25.

Creater.hs

@@ -13,8 +13,9 @@ import qualified System.Random.Shuffle as Shuffle
 
 create :: Random.StdGen -> [[Int]] -> Puzzle
 create rnd layout =
-  let puzzle = randomSolvedPuzzle rnd
-      layout' = shuffle rnd layout
+  let (rnd1, rnd2) = Random.split
+      puzzle = randomSolvedPuzzle rnd1
+      layout' = shuffle rnd2 layout
   in create' puzzle layout'
 
 create' :: Puzzle -> [[Int]] -> Puzzle