Update scaffolding for chromeapp permission

I've updated scaffolding for chromeapp permissions. chrome app has been updated so many. 

So I made `manifest.js` to manage manifest.json file, and To share with chrome-extension generator. and then changed the sequence of prompts for scaffolding. for clearly.

- Permission scenario changed. supports all of chromeapp permissions
- Permission sub-generator added.

Please let me know if it has a some problem or you have any suggestion.