README.md: Clarify that Clickhouse TCP is supported

[Zocker1999NET]

which is different from Clickhouse HTTP & Clickhouse gRPC, see https://clickhouse.com/docs/interfaces/tcp

I inferred that nebula only supports Clickhouse TCP from the fact that I cannot use it on my Clickhouse instance with TCP port 9000 blocked, and that nebula uses 9000 as its default port for Clickhouse DBs, which use that port for TCP by default (src).

[dennis-tra]

Hi @Zocker1999NET , nebula actually supports the native protocol in both encrypted (port 9440) and unencrypted (port 9000) ways. So putting in the readme just "Clickhouse TCP" is misleading because the specificity implies sole support for the unencrypted port. I'd rather leave it as it is but if you have other ideas how to make it clearer, I'm all ears 👍

[Zocker1999NET]

Thanks for your quick answer. Then I might rewrite it to "Native (unencrypted & encrypted)" or something like that?

The important point at least for me is that Nebula does not (yet) support the HTTP protocol, which I would say is fine, but was a hurdle for me because the database I am currently need to work with is only exposed to me through HTTP for some reason.