Add Typescript definitions for listenToKeyboardEvents

[leonid-shevtsov]

It's great that this package ships with TS definitions, but the function was missing from them.

It's tricky to properly type a HOC that returns a component with an API; but I found a way that works.

One inconvenience is that with a curried HOC Typescript cannot infer the types of the props, and you would have to define them explicitly:

listenToKeyboardEvents<ScrollViewProps>(options)(ScrollView)

[anthowm]

Could we merge this one for fix type issues ?

[pelayomartinez]

Would also love to see this merged!