In the case of disabled stub listeren the list of name servers is unordered. The solution is to configure the resolv.conf file directly instead of dbus API.
Because third-party services also can manipulate the DNS settings the agent watch the resolv.conf file and keep it up to date.
- apply file type DNS manager if in the name server list does not exist the 127.0.0.53 address
- watching the resolv.conf file with inotify service and overwrite all the time if the configuration has changed and it invalid
- fix resolv.conf generation algorithm
