Documentation is missed

[g4s8]

We need some simple documentation with usage examples with server configuration parameters and entry point classes.

[0crat]

@g4s8/z I'm not managing this repo, remove the webhook or contact me in Slack, as explained in §11; I'm not managing artipie/vertx-server GitHub repository, you have to contact me in Slack first, see §11 /cc @yegor256/z

[g4s8]

@Sammers21 please check this issue