Listen on internal IPv6

data/conf/nginx/templates/listen_plain.template

@@ -1 +1,2 @@
 listen ${HTTP_PORT};
+listen listen [::]:${HTTP_PORT};

data/conf/nginx/templates/listen_ssl.template

@@ -1 +1,2 @@
 listen ${HTTPS_PORT};
+listen listen [::]:${HTTPS_PORT};