Rewrite command system

[Artuto]

Discord has decided to restrict message content access to a privileged intent, however, we cannot apply for this because,

To be approved for verification to use message content, a bot's use-case for accessing message content must:

[...]

• cannot be feasibly migrated to our new interaction options;

[...]

tl;dr: if you request the intent because you do not want to migrate to slash commands it will get denied.

Since this bot does not use message content for anything else than commands and JDA Utils is dead the command system will need a rewrite.