Fixed null pointer exception when a boat finishes the race.

Boats now default to have position (0, 0).
Added mark rounding data to single player race.xml

racevisionGame/src/main/java/visualiser/Controllers/HostController.java

@@ -47,7 +47,7 @@ public class HostController extends Controller {
      */
     public void hostGamePressed() throws IOException{
         try {
-            Event game = new Event(true);
+            Event game = new Event(false);
             game.start();
             connectSocket("localhost", 4942);
         } catch (EventConstructionException e) {