Changed race clock to display negative time before race

#story[16] #implement

src/main/java/seng302/Model/Race.java

@@ -114,13 +114,17 @@ public abstract class Race implements Runnable {
 
         while (currentTime <= startTime) {
             timeLeft = startTime - currentTime;
-            currentTimeInSeconds = timeLeft / 1000;
-            minutes = currentTimeInSeconds / 60;
-            remainingSeconds = currentTimeInSeconds % 60;
-            hours = minutes / 60;
-            minutes = minutes % 60;
-            if (controller != null) {
-                updateTime(String.format("Time until race starts: %02d:%02d:%02d", hours, minutes, remainingSeconds));
+            if (timeLeft == 0 && controller != null) {
+                updateTime("Race is starting...");
+            } else {
+                currentTimeInSeconds = timeLeft / 1000;
+                minutes = currentTimeInSeconds / 60;
+                remainingSeconds = currentTimeInSeconds % 60;
+                hours = minutes / 60;
+                minutes = minutes % 60;
+                if (controller != null) {
+                   updateTime(String.format("Time until race starts: -%02d:%02d:%02d", hours, minutes, remainingSeconds));
+                }
             }
             try {
                 timeLoopEnded = System.currentTimeMillis();