Added .modchat for drivers.

I implemented a command strictly for a moderator ranked bot. The commands newly added are .modchatac, .modchatv and .modchatoff. These 3 commands allow drivers to turn on modchat if a Room Owner or moderator is not active. These commands I think will help room auth to allow themselves access and not contacting a global mod to just turn on mod chat.
What is even going on with ```text``` here? It's never being used, and doesn't actually do anything. All of your ```this.say``` commands have their message hardcoded, so it's not actually ever used, and ```'/modchat '+ '+';``` could be better represented by ```'/modchat +'```.