[xcbf] Example payload updated

I've updated my vendor specific payload
example to make it easier to follow and to
make the vendor associated with the biometric
data explicit.

<format>
   <!-- The format owner is Griffin Consulting -->
   <formatOwner> 2.23.42.9.10 </formatOwner>
   <formatType>
      <Account>
         <!-- The bank of this customer is Bigg Bank -->
         <bankIdentifier> 1.2.3.4.5.6.7.8.9 </bankIdentifier>
         <accountDigestInfo>
           <algorithmID>
              <!-- The hash algorithm is SHA-1 -->
              <algorithm> 1.3.14.3.2.26 </algorithm>
           </algorithmID>
            <accountHash>
               <!-- Here's the blinded customer account number -->
               0102030405060708091011121314151617181920
            </accountHash>
         </accountDigestInfo>
      </Account>
   </formatType>
</format>