Clarify APP_TRUSTED_PROXIES description in README

Author: LoveSkylark

README.md

@@ -126,7 +126,7 @@ linux/s390x
 * `REAL_IP_FROM`: Trusted addresses that are known to send correct replacement addresses (default `0.0.0.0/32`)
 * `REAL_IP_HEADER`: Request header field whose value will be used to replace the client address (default `X-Forwarded-For`)
 * `LOG_IP_VAR`: Use another variable to retrieve the remote IP address for access [log_format](http://nginx.org/en/docs/http/ngx_http_log_module.html#log_format) on Nginx. (default `remote_addr`)
-* `APP_TRUSTED_PROXIES`: Trusted proxies for Laravel / LibreNMS proxy awareness (default `172.17.0.0/16`)
+* `APP_TRUSTED_PROXIES`: Reverse proxy addresses trusted to forward the real client IP (default 172.17.0.0/16)
 * `SESSION_DRIVER`: [Driver to use for session storage](https://github.com/librenms/librenms/blob/master/config/session.php) (default `file`)
 * `CACHE_DRIVER`: [Driver to use for cache and locks](https://github.com/librenms/librenms/blob/master/config/cache.php) (default `database`)