minor #13714 Nginx dev config (Herz3h)

This PR was merged into the 3.4 branch.

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Nginx dev config

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Commits
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66ee17e Nginx dev config

Author: javiereguiluz

setup/web_server_configuration.rst

@@ -264,6 +264,7 @@ The **minimum configuration** to get your application running under nginx is:
 
         location / {
             # try to serve file directly, fallback to app.php
+            # replace app.php by app_dev.php in dev
             try_files $uri /app.php$is_args$args;
         }
         # DEV