implemented toString method

src/cards/Rank.java

@@ -13,7 +13,35 @@ public enum Rank {
      */
     @Override
     public String toString() {
-        //TODO implement
+        switch (this) {
-        return super.toString();
+            case TWO:
+                return "2";
+            case THREE:
+                return "3";
+            case FOUR:
+                return "4";
+            case FIVE:
+                return "5";
+            case SIX:
+                return "6";
+            case SEVEN:
+                return "7";
+            case EIGHT:
+                return "8";
+            case NINE:
+                return "9";
+            case TEN:
+                return "10";
+            case JACK:
+                return "J";
+            case QUEEN:
+                return "Q";
+            case KING:
+                return "K";
+            case ACE:
+                return "A";
+            default:
+                return "";
+        }
     }
 }