Explicitly add unrar to the live cd, and install wireshark setuid

These changes explicitly add unrar to the live ISO, even though it currently does the right thing, since we want unrar over unar, lets make sure we always have it on the ISO.

Also, lets install wireshark setuid now that we have a normal user, and make sure that the kali user on the live ISO as well as the installed user that users create during installation get added to the wireshark group so they can capture traffic without having to run wireshark as root or via pkexec/sudo.