v2.2.0: char sprites are now drawn in order from top to bottom

SPD-classes/src/main/java/com/watabou/noosa/Group.java

@@ -25,6 +25,8 @@ import com.watabou.utils.Random;
 import com.watabou.utils.Reflection;
 
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
 
 public class Group extends Gizmo {
 
@@ -310,4 +312,8 @@ public class Group extends Gizmo {
 			return null;
 		}
 	}
+
+	public synchronized void sort(Comparator c){
+		Collections.sort(members, c);
+	}
 }