✨ Allow using debug directives, enable --with-debug compile option

[agconti]

This allows debug information to be accessed by adding this directive to nginx.conf:

error_log /var/log/nginx/error.log debug;

This is the recommended way based on the nginx-rtmp-module wiki: https://github.com/arut/nginx-rtmp-module/wiki/Debug-log

[tiangolo]

Great, thanks! 🚀

Sorry for the long delay! 🙈 I wanted to personally address each issue/PR and they piled up through time, but now I'm checking each one in order.