Added one extra tidbit of logging for GameMode enforcement.

src/main/java/com/onarandombox/MultiverseCore/listeners/MVPlayerListener.java

@@ -311,6 +311,9 @@ public class MVPlayerListener implements Listener {
         MultiverseWorld mvWorld = this.worldManager.getMVWorld(world.getName());
         if (mvWorld != null) {
             this.handleGameMode(player, mvWorld);
+        } else {
+            this.plugin.log(Level.FINER, String.format(
+                    "Not handling gamemode for world '%s' not managed by Multiverse.", world.getName()));
         }
     }