Modify DigestMethod of EncryptedKey

[Cantor, Scott]

If it helps spot something, this is being used in our Eclipse testbed and works:

            <md:EncryptionMethod Algorithm="http://www.w3.org/2009/xmlenc11#rsa-oaep">
                <MGF xmlns="http://www.w3.org/2009/xmlenc11#"
                    Algorithm="http://www.w3.org/2009/xmlenc11#mgf1sha256" />
                <DigestMethod xmlns="http://www.w3.org/2000/09/xmldsig#"
                    Algorithm="http://www.w3.org/2001/04/xmlenc#sha256" />
            </md:EncryptionMethod>

The md prefix is SAML's usual, the rest of the elements are from the namespaces you'd expect/need.

-- Scott