[Feature/Optimization Request] Stop shading packetevents

[rafi67000]

Hi!
It's better to depend on external packetevents due to (for example):

1. users can manually update packetevents (for example to dev build with hotfixes)
2. better performance (packets have to be encoded/decoded multiple times)
3. smaller jar size

[Pyrbu]

The only reason we aren't currently using external packet events is that I'm personally against having to install "dependency" plugins for the simple reason that it introduces more issues when installing the plugin for users which means we need to provide more support.

I've also looked into supporting both the plugin and the shaded version but the issue with that is the plugin would need to load the classes at runtime if the plugin isn't present which is currently almost impossible due to Paper's decision to remap plugins at server start time.