Big refactoring

I have replaced all callbacks with async/await functions.
[Braking change] - Parameter appID was changed to appId
[Braking change] - Default facebook version is v2.9
[Braking change] - Login has two parameters onError and onResponse instead of just onResponse
Login and Share component has two new properties "render" and "component". You can use your own components with this "high-order-components". You can find example in the readme
Use babel polyfill for backward compatibility with older browsers