Update Readme with configuration example

README.md

+### `LocalSettings.php` configuration example
+
+~~~PHP
+require_once('extensions/ShibAuthPlugin.php');
+
+//Allow for empty paswords
+$wgMinimalPasswordLength = 0;
+
+// Last portion of the shibboleth WAYF url for lazy sessions.
+// This value is found in your shibboleth.xml file on the setup for your SP
+// WAYF url will look something like: /Shibboleth.sso/WAYF/$shib_WAYF
+$shib_WAYF = "";
+
+//Are you using an old style WAYF (Shib 1.3) or new style Discover Service (Shib 2.x)?
+//Values are WAYF or DS, defaults to WAYF
+$shib_WAYFStyle = "DS";
+
+// Default for compatibility with previous version: false
+$shib_Https = true;
+
+// Prompt for user to login
+$shib_LoginHint = "Login with SSO";
+
+// Prompt for user to log out
+$shib_LogoutHint = "Logout";
+
+// Where is the assertion consumer service located on the website?
+// Default: "/Shibboleth.sso"
+$shib_AssertionConsumerServiceURL = "/Shibboleth.sso";
+
+// Map Real Name to what Shibboleth variable(s)?
+$shib_RN = isset($_SERVER['HTTP_COMMON_NAME']) ? $_SERVER['HTTP_COMMON_NAME'] : null;
+
+// Map e-mail to what Shibboleth variable?
+$shib_email = isset($_SERVER['HTTP_EMAIL']) ? $_SERVER['HTTP_EMAIL'] : null;
+
+// The ShibUpdateUser hook is executed on login.
+// It has two arguments:
+// - $existing: True if this is an existing user, false if it is a new user being added
+// - &$user: A reference to the user object. 
+//           $user->updateUser() is called after the function finishes.
+// In the event handler you can change the user object, for instance set the email address or the real name
+// The example function shown here should match behavior from previous versions of the extension:
+
+$wgHooks['ShibUpdateUser'][] = 'ShibUpdateTheUser';
+
+function ShibUpdateTheUser($existing, &$user) {
+        global $shib_email;
+        global $shib_RN;
+        if (! $existing) {
+                if($shib_email != null)
+                        $user->setEmail($shib_email);
+                if($shib_RN != null)
+                        $user->setRealName($shib_RN);
+        }
+        return true;
+}
+// This is required to map to something
+// You should beware of possible namespace collisions, it is best to chose
+// something that will not violate MW's usual restrictions on characters
+// Map Username to what Shibboleth variable?
+$shib_UN = isset($_SERVER['HTTP_UID']) ? $_SERVER['HTTP_UID'] : null;
+
+# hide "IP login" and default login link
+$wgShowIPinHeader = false;
+function NoLoginLinkOnMainPage( &$personal_urls ){
+    unset( $personal_urls['login'] );
+    unset( $personal_urls['anonlogin'] );
+    return true;
+}
+$wgHooks['PersonalUrls'][]='NoLoginLinkOnMainPage';
+
+// Activate Shibboleth Plugin
+SetupShibAuth();
+~~~