try_bind should return a Future (or its docs are inconsistent)

[abreis]

I was going through server.rs and noticed that Server::try_bind says:

(...) returning a Future that can be executed on any runtime.

but it actually ends in .await; and returns nothing.

I dug around a bit and it did return a Future in the original PR in #250 (which is consistent with the behavior of bind(), but #265 changed that behavior. I can't tell if it that change was intentional or a lapse, so I'm only reporting the inconsistency.

[abreis]

Same with TlsServer::bind (which actually makes it inconsistent with Server::bind).

[ivan]

Don't all async functions return a Future?

[abreis]

Nevermind, I missed the fact that Server::bind is a plain fn but the others are async fns.