Tests: use 127.0.0.1 instead of localhost.

Name 'localhost' is ambiguous if ipv6 present on system.

lib/Test/Nginx.pm

diff --git a/lib/Test/Nginx.pm b/lib/Test/Nginx.pm
index d5df67f..e386949 100644
--- a/lib/Test/Nginx.pm
+++ b/lib/Test/Nginx.pm
@@ -212,7 +212,7 @@
 		alarm(2);
 		my $s = IO::Socket::INET->new(
 			Proto => 'tcp',
-			PeerHost => 'localhost:8080'
+			PeerAddr => '127.0.0.1:8080'
 		);
 		log_out($request);
 		$s->print($request);