Moderation case system

[rasmusgerdin]

Implementation of a moderation case system, storing information on all moderator actions taken on a server. Current implementation can be seen here.

I think it would be interesting to improve on the implementation this time around, allowing for actions to be taken on specific cases after they've happened (such as reversing a ban by directly referencing the case). Possibly allow the user who had action taken against them to appeal it?

To note, this issue is only for the implementation of the case system itself as opposed to any commands or log events related to it.

This is dependent on #230.