1. change the way for extending HelperBar.
   when is in safe mode, user only can extend the method is not in
   Helpbar.
   when is in unsafe mode, user can overwrite the existed mehtod on Helpbar.
1. add extend so HelperBar.fn.extend can extends methods.
2. demo add HelperBar.fn.extend
3. demo has 3 more extend example:
rainbowMsg,flashRainbowMsg,realRainbowMsg
1.adjust demo.js code
1. adjust demo.js