Feature: Multiplayer

[RameshRavone]

Implement Google Multiplayer service.

[benkaranja]

Hey @RameshRavone

This module https://github.com/kloder-games/godot-gpgs actually plays well with your module. I just added the realtime multiplayer class and with abit of trial and error got it to work.

[RameshRavone]

Thanks, I'll look into thing's and a PR would be nice,