Feature request: Let socket.close() return a Future

[slovdahl]

A simple request, let socket.close() return a Future that can be used to block the current thread until the connection is properly closed.

[coopstah13]

Isn't this more of a bug? The javadoc states that close is async.

[jfarcand]

@coopstah13 If you have the cycle feel free to submit a patch!