API for wrapping Node.js EventEmitters safely

[bordoley]

https://nodejs.org/api/events.html

also see: ReactiveX/rxjs#2533

There's some weirdness in particular with how node handles errors.

[bordoley]

EventEmitters are a minefield that won’t play well in general with reactive’s pure async api. The best option for users is to connect manually to an event emitter and use a SubjectLike or EventLike to publish events downstream where appropriate.