avoid out of bounds

lazpaint/image/uimage.pas

@@ -1998,6 +1998,8 @@ procedure TLazPaintImage.MoveLayer(AFromIndex, AToIndex: integer);
 begin
   if (AFromIndex < 0) or (AFromIndex >= NbLayers) then
     raise exception.Create('Index out of bounds');
+  if AToIndex < 0 then AToIndex := 0;
+  if AToIndex >= NbLayers then AToIndex := NbLayers-1;
   if not CheckNoAction then exit;
   try
     AddUndo(FCurrentState.MoveLayer(AFromIndex,AToIndex));