Add forwarding system

[xism4]

This pull request comes from the other one not accepted due to some factors that were fixed here

• Added 1.19 and 1.20 support
• Cut down excesive logg-in
• Tested all the modes (Velocity_forwarding with modern backends, Legacy one and BungeeGuard)

@electronicboy

You can read what this adds on https://github.com/PaperMC/Waterfall/pull/663

[xism4]

Ignore patch error, it's just a editor issue because im not that friendly with patches.