[hueemulation] Fix nginx example configuration

[DieserMerlin]

Fix nginx example configuration

Just a little fix in an example configuration. Nginx won't start with the previous example what confused me when I tried to set up a reverse proxy.

Also please consider highlighting the following part:

server {
  listen 80;
  location /api {
    proxy_pass http://localhost:8080/api/;
  }
}

I struggled a lot since I didn't read this and my Alexa couldn't find my emulated devices.

[MikeJMajor]

LGTM