v1.5.0 code-review request

ref: https://github.com/leecade/react-native-swiper#changelogs

There are two Major changes:

1. Adjust project structure, publish with src file, use watch-copy script and relative dependencies for improve develop workflow

   "dependencies": {
       "react-native-swiper": "../"
   },
   

2. ES6 syntex and standard[https://github.com/feross/standard] code style

Please help for more tests and code review, then release 1.5.0, thanks a lot.

@rajkissu @sunnylqm @tasiyo7333 @getnashty