Update to the README.

Author: jlesage

README.md

@@ -534,6 +534,15 @@ server {
 		proxy_set_header Connection $connection_upgrade;
 		proxy_read_timeout 86400;
 	}
+
+	# Needed when audio support is enabled.
+	location /websockify-audio {
+		proxy_pass http://docker-firefox;
+		proxy_http_version 1.1;
+		proxy_set_header Upgrade $http_upgrade;
+		proxy_set_header Connection $connection_upgrade;
+		proxy_read_timeout 86400;
+	}
 }
 
 ```