Add Discord RPC support

[feikname]

RPC (Rich PresenCe) is a Discord feature for adding more info to the "Playing" card of users. In OpenSpades case, relevant info could be the server's name and user's play time on that server.

For now, RPC is in a private beta, which means that only apps that have signed up and been approved can access it.

Using this feature would require the creation of an app inside the Discord developers dashboard.

Relevant links:

• https://github.com/discordapp/discord-rpc
• https://discordapp.com/developers/docs/topics/rpc

[NotAFile]

I could have sworn this was an issue already

[tomlister]

This is possible with https://discord.com/developers/docs/game-sdk/activities