Introduce Discord login (oauth2)

[Crystalwarrior]

Allow people to log in thru discord, giving them various benefits such as obtaining the gm/mod role etc. Doing away with needing passwords

[stonedDiscord]

I've tried that before and you'd have to add a https server with a valid certificate first

[axestyra]

#174

Mod logins were implemented in a similar way for the whitelist system.