Add /kick, /ban and /mute commands

[Xarlos89]

/kick - Kicks a user, be sure to have a reason
/ban - Bans a user, be sure to have a reason
/mute - Mutes a user, be sure to have a reason

On all 3, make sure we send a PM to the user with the reason, and the timespan, as well as a way to appeal.