Create discord-rpc-godot

[Lachee]

Godot seems to be a very popular tool now, there should be a port of this library like lachee/discord-rpc-unity that supports Godot

Looking for anyone who is willing to put the time into this.

Notes

• Since Godot is Mono, you will need to use the UnityNamedPipe from the Unity project.

[sitiom]

Related issue: #94. With Godot 4 using .NET 6, this shouldn't be needed anymore.

You might want to keep this issue open if you still want to support Godot 3.