Replaces the old OpenSSL algorithmic constants with the newer strings initializers.

Author: withshubh

lib/xml_security.rb

@@ -218,7 +218,7 @@ def validate_document(idp_cert_fingerprint, soft = true, options = {})
         if options[:fingerprint_alg]
           fingerprint_alg = XMLSecurity::BaseDocument.new.algorithm(options[:fingerprint_alg]).new
         else
-          fingerprint_alg = OpenSSL::Digest::SHA1.new
+          fingerprint_alg = OpenSSL::Digest.new('SHA1')
         end
         fingerprint = fingerprint_alg.hexdigest(cert.to_der)