Improve Node.js server shutdown and error handling

[armanbilge]

Just some minor tweaking to make the code a bit nicer.

More importantly, I think this suffers from same/similar problems as #2300, namely: how do you gracefully shutdown/handle errors? The critical thing seems to be that any sockets remaining in the queue should be destroyed.

Perhaps I'm missing something, but it seems to me that the problem lies with the server method. With the serverResource method, I can conceptualize the "listening" part of the server being tied to the resource, so that even after the resource is closed the stream of sockets is still usable. But maybe this is leaky?

cc @RaasAhsan

[mpilquist]

@armanbilge Does this PR change the behavior to match the JVM version?

[armanbilge]

Hmm, a bit fuzzy since I made this. It makes two changes:

1. The use of Async instead of a Deferred to handle errors at server creation. This should just be code cleanup.
2. Use a None-terminated Queue of Sockets (the previous was unterminated). A None is added to the queue when the server resource is closed.

What is still an open problem is how to guarantee that all the sockets are destroyed. Right now, if they are unconsumed by the Stream, they will sit open in the queue indefinitely.

Does this PR change the behavior to match the JVM version?

Not sure, what exactly does the JVM side do?