[Feature] Add punycoded versions for IDN domains

Issue: #554
Reported by: @moisseev

contrib/publicsuffix/idn.pl

@@ -0,0 +1,20 @@
+#!/usr/bin/env perl
+
+use warnings;
+use strict;
+use Net::IDN::Encode ':all';
+use Unicode::Normalize;
+
+binmode(STDOUT, ":utf8");
+binmode(STDIN, ":utf8");
+
+while (<>) {
+	$_ = NFC($_);
+	if (/^[^\/].*[^\x00-\x7F]+.*/) {
+		chomp;
+		printf "%s\n", domain_to_ascii($_);
+		$_ .= "\n";
+	}
+} continue {
+	print $_;
+}