Ability to add channel bans

[S-S-X]

Ban players from channels as more permanent solution for some players who just cannot manage to use main chat channels nicely but do not necessarily have to be banned completely from using most chat features or playing on server.

Channel ban should simply disallow players from using selected channels while still allowing other chat features, something between /chat_jail and unrestricted chat.

Possibly with shortcut command to ban players from all main channels like for example #main, #en, #ru, #de, #fr
Having basic stuff from #12 would probably also help with this one.

[S-S-X]

Related update #32 tries to offer rewards instead of punishment.

[S-S-X]

Possibly allow enforcing message rate limits for players instead of complete banning from channels.

Channel bans could still be useful for some special cases but I think setting channel message rate limits as milder version of ban would be very good idea, that would encourage thinking what you want to actually say and encourage using other chat channels for chatting without completely rejecting player from channel.

[SwissalpS]

there seems to be a need for channel owners to be able to kick players from channels.
a 'force_leave' command could work for password protected channels, but would have to also change password in same command.

somewhat related: there is no 'change_password' command. Maybe 'change_atributes' might be better, so that colour could also be changed without having to delete and recreate the channel.