This adds cjdns-tools which is exposing the tools from
$cjdns/tools/ under a command named cjdns-tools
(so for ex cjdns "ping" is accessible as cjdns-tools ping <ip>)
Additionally patches cjdns tools to read admin pw from /etc/cjdns.keys
Co-authored-by: Sandro <sandro.jaeckel@gmail.com>
