IDEA. consider using PromiseLike interface instead of Promise class

[snytkine]

This means that there will not be a .catch usage anywhere. Instead, the .then will accept a second function to handle error.
This way a middleware can have 2 functions: doFilter like it does not and onError(e: any) => Promise

One benefit is that errorFormatter becomes just a middleware instead of a function that goes inside .catch at the end.
Another benefit is that a middleware may exist somewhere in the middle of promise chain and be able to recover from error.

Another benefit is ability to switch to different Promise provider like BlueBird