updated swap:withNewIndex: in CCSpriteBatchNode.m

textureAtlas quads are not updated to reflect changes to the atlas index of a swapped object. in consequence the draw order does not change. 

related to issue #598.

Former-commit-id: 48de06e

Author: kalo

cocos2d/CCSpriteBatchNode.m

@@ -337,6 +337,10 @@ - (void) swap:(NSInteger) oldIndex withNewIndex:(NSInteger) newIndex
     //update the index of other swapped item
 	( ( CCSprite* )[ _descendants objectAtIndex:newIndex ] ).atlasIndex = oldIndex;
     [_descendants exchangeObjectAtIndex:oldIndex withObjectAtIndex:newIndex];
+    
+    // update the quads for the swapped sprites in the textureAtlas (issue #598)
+    _textureAtlas.quads[newIndex] = [(CCSprite *)[_descendants objectAtIndex:newIndex] quad];
+    _textureAtlas.quads[oldIndex] = [(CCSprite *)[_descendants objectAtIndex:oldIndex] quad];
 }
 
 - (void) reorderBatch:(BOOL) reorder