Distributed ban list

[karashiiro]

The ban list should be shared across instances using some sort of distributed store, like TiDB. Some sort of hook will be needed to read the server's ban lists into the database, and read bans back from the database.

[karashiiro]

See #11, a hook should not be used for this.

[karashiiro]

I have been informed that TiDB is not appropriate here. It's still MariaDB time.

[karashiiro]

I might create new data folders for each instance and set up a watch on those folders that writes to the database appropriately. When new data folders are created, they'll be populated from the database.

[karashiiro]

I should also create a tool that seeds the DB from an existing ban list for migration purposes.

[karashiiro]

This might be better generalized as a generic settings sync, perhaps through some diff algorithm, or even just Git.