propose a v2 api

[dominictarr]

Trying to make this ready to actually use, I want to suggest these changes.

To create a connection it must take a callback,
you could return a stream, but then you get ECONREFUSED errors in the stream,
which probably means the error ends up in a part of the app that doesn't know how to handle that error.
Also, this is simpler.

Some complication is added when you connect to a domain name - it has to do a lookup,
you can actually return the stream sync on the client and the server if you don't need a lookup.

[dignifiedquire]

👍 on moving to a callback, I went back and forth over this in my head, but in the head using a callback instead of immediately returning a stream makes it much easier to separate the concerns of error handling as you mention.