Script to generate polkadot-js app

[xlc]

Script to perform this
https://github.com/polkadot-js/apps/blob/master/packages/app-123code/README.md

[shawntabrizi]

Fixed with #25

[xlc]

This is different issue. #25 clones polkadot apps project. This one is use the app-123code package as template to generate a new one by perform the 6 steps in that readme file.