Swarm Sonata - First Multiplayer build

I have rewritten the game from scratch because I wanted to add multiplayer features, and my previous code was not that great.

This new build is the first playable multiplayer build with direct connecion (even if there is very few things to do and just 2 weapons) and is focused on making things work. It's just a POC as it is right now.

More to come in the future (if I do not get lost again in my other side projects...)