Added support to OS (kali linux for example) that using iptables nf_tables

[mh4x0f]

Hi, many S.O like kali linux is come from with iptables with support nf_tables by default, that is bad the top set iptables rules. For solve this, I put a patch to find the iptables version and if is with nf_tables support set the legacy iptables iptables-legacy version as default patch binary.

the version legacy all rules write for old iptables willl be work fine.

Thanks for all, mh4x0f