[RFE] Add parameters to enable SNI

[Gsantomaggio]

It would be useful to have parameters to enable SNI and set the SNI value on TLS.

Most of the k8s ingresses support the SNI match to redirect the traffic, see rabbitmq/tgir#20

At the moment to test rabbitmq/tgir#20 I am using this test client

cc @gerhard

[gerhard]

What do you think @acogoluegnes?

[acogoluegnes]

Sure, that's possible. What kind of values do you expect for the server names, nothing fancy? I guess comma-separated values would work.

The only trick is to make it work for both blocking IO (with a SocketConfigurator) and NIO (like in the example), with a SslEngineConfigurator). This would be transparent for the user.

[Gsantomaggio]

I guess comma-separated values would work

Yes, I think so!