Pull request: 2231 autoupdate

Merge in DNS/adguard-home from 2231-autoupdate to master

Updates #2231.

Squashed commit of the following:

commit 4ee9148ee7a38f2759898302a2109aa982fb4ee9
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Mon Nov 30 19:08:14 2020 +0300

    sysutil: provide os-independent interface

commit 778097c5fdeb1dec94f4cfc6443d08f92d9db0ba
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Mon Nov 30 16:40:33 2020 +0300

    all: add sysutil package

internal/sysutil/syslog_others.go

@@ -0,0 +1,17 @@
+//+build !windows,!nacl,!plan9
+
+package sysutil
+
+import (
+	"log"
+	"log/syslog"
+)
+
+func configureSyslog(serviceName string) error {
+	w, err := syslog.New(syslog.LOG_NOTICE|syslog.LOG_USER, serviceName)
+	if err != nil {
+		return err
+	}
+	log.SetOutput(w)
+	return nil
+}