|alex cheng||the addChild of CCParallaxNode have one bug for lua|
for tulua++ in luacocos2d.cpp is :
when call CCNode::addChild in CCParallaxNode::addChild, z will convert to int, but it's not same with the value writed in lua codes.
On windows and ios simulator,it work well.
So, the addChild of CCParallaxNode should be defined as below: