Update Single_Sign-on_to_Azure_AD_using_SimpleSAMLphp.md

Single_Sign-on_to_Azure_AD_using SimpleSAMLphp/Single_Sign-on_to_Azure_AD_using_SimpleSAMLphp.md

@@ -181,6 +181,7 @@ Now that configuration of SimpleSAMLphp is complete, we can use SimpleSAMLphp to
 So, all this configuration was just to get us to the point where we can create our own application code that allows us to authenticate with Azure AD. The reality is that our PHP “application” can be a single page.
 
 ## index.php
+Generally, the application will require an index.php file – the code for which is below. I’ll give a very brief breakdown of the first few lines, the rest is obvious.
 ```php
 <?php
 require_once (dirname(__FILE__) . '/../simplesamlphp/lib/_autoload.php');