Create class Sudoku9x9, model of Sudoku game
with built-in setSample method to use sample on 
http://en.wikipedia.org/wiki/Sudoku
--- index ---
 1  2  3  4  5  6  7  8  9 
10 11 12 13 14 15 16 17 18 
19 20 21 22 23 24 25 26 27 
28 29 30 31 32 33 34 35 36 
37 38 39 40 41 42 43 44 45 
46 47 48 49 50 51 52 53 54 
55 56 57 58 59 60 61 62 63 
64 65 66 67 68 69 70 71 72 
73 74 75 76 77 78 79 80 81 
--- value ---
 5  3  .  .  7  .  .  .  . 
 6  .  .  1  9  5  .  .  . 
 .  9  8  .  .  .  .  6  . 
 8  .  .  .  6  .  .  .  3 
 4  .  .  8  .  3  .  .  1 
 7  .  .  .  2  .  .  .  6 
 .  6  .  .  .  .  2  8  . 
 .  .  .  4  1  9  .  .  5 
 .  .  .  .  8  .  .  7  9