Revise NO_LOCAL_CHECK docs, a=chris

diff --git a/en-US/pages/documentation.thtml b/en-US/pages/documentation.thtml
index a53fff3..b8b2bde 100755
--- a/en-US/pages/documentation.thtml
+++ b/en-US/pages/documentation.thtml
@@ -536,7 +536,7 @@ to set up Yioop!) where it is difficult to connect using localhost, you can
 add a file, configs/local_configs.php, with the following content:</p>
 <pre>
 &lt;?php
-define('NO_LOCAL_CHECK', true);
+define('NO_LOCAL_CHECK', 'true');
 ?&gt;
 </pre>
 <p> Returning to our installation discussion, notice under the text field there