Move settings that don't differ per container to the top level

nginx.tmpl

@@ -12,6 +12,15 @@ map $http_upgrade $proxy_connection {
   ''      '';
 }
 
+# HTTP 1.1 support
+proxy_http_version 1.1;
+proxy_set_header Host $http_host;
+proxy_set_header Upgrade $http_upgrade;
+proxy_set_header Connection $proxy_connection;
+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 $proxy_x_forwarded_proto;
+
 server {
 	listen 80 default_server;
 	server_name _; # This is just an invalid value which will never trigger on a real hostname.
@@ -64,15 +73,6 @@ server {
 
 	location / {
 		proxy_pass http://{{ $host }};
-		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 $proxy_x_forwarded_proto;
-
-		# HTTP 1.1 support
-		proxy_http_version 1.1;
-		proxy_set_header Upgrade $http_upgrade;
-		proxy_set_header Connection $proxy_connection;
 	}
 }
 {{ end }}