Released version 3.11.6

* iptables: security update (CVE-2019-11360)
* knot-resolver, netdata, youtube-dl, foris, sentinel-certgen, wireguard, python3-idna, kernel: update
* resolver-conf: add secondary IP for DNS server (IPv4 and IPv6)
* turris-netboot: minor fixes and add parameter force
* dev-detect: introduce a new lightweight version than pakon-dev-detect (opt-in)