Servers white/black list

I suggest adding a whitelist/blacklist option for servers as well. That is, if:
- e.g. the "lobby" server is blacklisted, a kicked player from the lobby server will not be redirected to the servers-to-redirect, but completely kicked out of the server.
- e.g. the "survival" server is whitelisted, a kicked player from the survival server will be redirected to the servers-to-redirect

The plugin handles server kick redirection; look for the main plugin class and the event listener for player kicks. Understand how the current redirection logic works and where server lists are managed. The change involves adding a whitelist/blacklist check before redirecting a kicked player.

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