public void destroyRoom(JID alternateJID, String reason) {
        destroyRoom(alternateJID,  null, reason);
    }
Destroys the room. Each occupant will be removed and will receive a presence stanza of type
"unavailable" whose "from" attribute will be the occupant's nickname that the user knows he
or she has been removed from the room.

@param alternateJID an optional alternate JID. Commonly used to provide a replacement room. (can be {@code null})
@param reason an optional reason why the room was destroyed (can be {@code null}).
xmppserver/src/main/java/org/jivesoftware/openfire/muc/MUCRoom.java