Closes #1381. Squashed commit of the following: commit 44965f74d8becb27173cafc533e56e1cde484b59 Author: Ainar Garipov <A.Garipov@AdGuard.COM> Date: Thu Jun 17 13:54:44 2021 +0300 dnsforward: imp code, docs commit 23736cf9b407b668faade19b61739536caafff03 Author: Ainar Garipov <A.Garipov@AdGuard.COM> Date: Wed Jun 16 20:33:59 2021 +0300 dnsforward: rm todo commit ff086756160d72f3cdbe662862dd1fb447ac5ff3 Author: Ainar Garipov <A.Garipov@AdGuard.COM> Date: Wed Jun 16 20:32:01 2021 +0300 all: sup many ips in host rules