Fixed the code in the boxComplete method, which was to check north and south...

Fixed the code in the boxComplete method, which was to check north and south horizontal lines and east and west vertical lines in-order to determine if the box is complete or not.

src/main/java/dotsandboxes/DotsAndBoxesGrid.java

@@ -117,8 +117,11 @@ public class DotsAndBoxesGrid {
 
         // A box is complete if the north and south horizontals and the east and west verticals have all been drawn.
         // FIXME: You'll need to fix this code (after writing a test first).
+        if ((getHorizontal(x, y) && getHorizontal(x, y + 1)) && (getVertical(x, y) && getVertical(x + 1, y))) {
             return true;
         }
+        return false;
+    }
 
     /** Tries to claim a box for a player. If the box is complete, sets the ownership and returns true. */
     private boolean claimBox(int x, int y, int p) {