r/minio-nginx: Reverse proxy for MinIO

The *minio-nginx* role configures nginx to proxy for MinIO.  It uses the
"subdomain" pattern, as described in [Configure NGINX Proxy for MinIO
Server][0]; the S3 API and the console UI are accessible through
different domain names.

[0]: https://min.io/docs/minio/linux/integrations/setup-nginx-proxy-with-minio.html

roles/minio-nginx/templates/minio.nginx.conf.j2

@@ -0,0 +1,20 @@
+client_max_body_size 0;
+proxy_buffering off;
+proxy_request_buffering off;
+chunked_transfer_encoding off;
+
+proxy_connect_timeout 300;
+
+location / {
+    proxy_set_header Host $http_host;
+    proxy_set_header X-Real-IP $remote_addr;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto $scheme;
+
+    real_ip_header X-Real-IP;
+
+    proxy_http_version 1.1;
+    proxy_set_header Connection "";
+
+    proxy_pass http://127.0.0.1:{{ minio_port }};
+}