Async example

Quote from https://jaredforsyth.com/2017/06/23/when-will-reasonml-be-ready/:

> The OCaml community has some pretty fundamental fragmentations (there are three incompatible versions of the standard library, two incompatible ways to handle async), and documentation is generally pretty sparse. We’re hoping to establish good “batteries included” standard library (that will work for both js and native), but it will take some time.

To JS programmers, async pattern is very common nowadays, we are get used to it. Hence, been said that "there is no standard for async pattern in OCaml" made me worried how to convert my async codes into Reason counterpart.

It would be nice if there is a tutorial about how to do so in OCaml. (e.g. extend the Todo app to send the new item to a simple backend server)

Usa el artículo enlazado y el ejemplo de la aplicación Todo como puntos de partida; primero identifica el patrón async y cómo debería enviar la aplicación un elemento nuevo a un backend. Se considera terminado cuando haya un tutorial que explique ese flujo para lectores de Reason/OCaml y JavaScript, con suficientes pasos para seguirlo.

Escrito por el modelo de indexación a partir del texto del issue.