CORS issue with embedded nginx

[hbruch]

When qgis-server is started using the embedded nginx service, no object information is displayed as qgis-server does not send an Access-Control-Allow-Origin header.

This could be solved e.g. by adding add_header Access-Control-Allow-Origin *; to the /qgis/ location in qgis-server-nginx.conf.

[JakobMiksch]

not sure if this is the responsibility of the QGIS server, since it might be behind another proxy.
when adding this a CORS header to the conf, I would prefer it to be optional with default to false.