minor #1307 Don't rewrite requests for existing directories to index.php (arrgson)

This PR was submitted for the master branch but it was merged into the 1.3 branch instead (closes #1307).

Discussion
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Don't rewrite requests for existing directories to index.php

Commits
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5ce29424 Don't rewrite requests for existing directories to index.php

doc/web_servers.rst

@@ -14,6 +14,7 @@ following ``.htaccess`` file:
 
         RewriteEngine On
         #RewriteBase /path/to/app
+        RewriteCond %{REQUEST_FILENAME} !-d
         RewriteCond %{REQUEST_FILENAME} !-f
         RewriteRule ^ index.php [QSA,L]
     </IfModule>