[prerelease] Region sync setting, vistas fix, redis fix, netty relocation change

Hey folks! This is a small prerelease, mostly with some fixes that were setup as an incident response due to some issues on a network.

Vistas fix

Squashed a memory management issue within the vistas server, caused by an incorrect hashset keeping track of downcast ints with invalid hashes.

• Only the vistas-server module was effected, meaning that installations on Spigot, Paper, BungeeCord and Velocity are entirely unaffected

Netty relocation + Bungeecord

The last update used some hacky maven stuff to interact with internal bungeecord components to fix issues with connecting clients on 1.20.2+ (due to the new login configuration phase (https://wiki.vg/Protocol#Configuration). This ended up breaking lettuce (the redis library used for viastas-client to break. The new method undoes that change, and reimplements the original fix using some reflection which gets cached after the first player join on BungeeCord (lookups get cached after the first class access, no additional overhead is occurred)

Region settings

A new feature, configurable region synchronisation, is also included. This was originally a global config value, but can now be configured per region through the GUI. This does mean that there was a DB model update, which is not yet final. Changes made with this setting may be lost when upgrading to the full release.

Misc info

• This release is not advised for production use. Those who needed the fixes already received them from me personally as response to the issue, which has since hit production.
• All jars are targeted against java 8, just like regular releases.