Bugfixes, cleanup, optimization

core/src/io/anuke/mindustry/game/EventType.java

@@ -22,10 +22,19 @@ public class EventType {
         void handle();
     }
 
+    /**This event is called from the logic thread.
+     * DO NOT INITIALIZE GRAPHICS HERE.*/
     public interface WorldLoadEvent extends Event{
         void handle();
     }
 
+    /**Called after the WorldLoadEvent is, and all logic has been loaded.
+     * It is safe to intialize graphics here.*/
+    public interface WorldLoadGraphicsEvent extends Event{
+        void handle();
+    }
+
+    /**Called from the logic thread. Do not call graphics here!*/
     public interface TileChangeEvent extends Event{
         void handle(Tile tile);
     }