Add digestAlgorithm info on the Readme

Author: pitbulk

README.md

@@ -470,6 +470,13 @@ $advancedSettings = array (
         //    'http://www.w3.org/2001/04/xmldsig-more#rsa-sha512'
         'signatureAlgorithm' => 'http://www.w3.org/2000/09/xmldsig#rsa-sha1',
 
+        // Algorithm that the toolkit will use on digest process. Options:
+        //    'http://www.w3.org/2000/09/xmldsig#sha1'
+        //    'http://www.w3.org/2001/04/xmlenc#sha256'
+        //    'http://www.w3.org/2001/04/xmldsig-more#sha384'
+        //    'http://www.w3.org/2001/04/xmlenc#sha512'
+        'digestAlgorithm' => 'http://www.w3.org/2000/09/xmldsig#sha1',
+
         // ADFS URL-Encodes SAML data as lowercase, and the toolkit by default uses
         // uppercase. Turn it True for ADFS compatibility on signature verification
         'lowercaseUrlencoding' => false,