[ASIO] Do not give clients unbound endpoints.

If the user has configured specific endpoint to bind services to in the configuration file, actors
would still resolve local hostname and return every possible endpoint instead of using only the one
configured by the user.
[ASIO] Use bound acceptor's endpoint for logs.

Do not try to figure out acceptor's bound endpoints with resolvers and other magic, just use the
provided local_endpoint() method. Logging unspecified addresses is fine in that case.
[API] An ability to create connect-only Resolvers.

These resolvers do not actually resolve anything, but used only for client connections.