Integrated multiplayer server and client

**What do you want to see?**
The ability to host and play multiplayer games without relying on a third party service like PBW or manually emailing files around.

**How would it help players?**
Make multiplayer more intuitive and modern.

**Alternatives**
Create a PBW web service independent of FrEee and connect to that

**Screenshots and mockups**
N/A

**Things to consider**
Not sure yet...