code: @Nonnull
    public CSP2SourceList addHash (@Nonnull final EMessageDigestAlgorithm eMDAlgo,
                                   @Nonnull @Nonempty final byte [] aHashValue)
    {
      ValueEnforcer.notEmpty (aHashValue, "HashValue");
      return addHash (eMDAlgo, Base64.safeEncodeBytes (aHashValue));
    }
docs: Add the provided nonce value. The {@value #HASH_PREFIX} and
  {@link #HASH_SUFFIX} are added automatically. The byte array is automatically
  Bas64 encoded!
  
  @param eMDAlgo
  The message digest algorithm used. May only
  {@link EMessageDigestAlgorithm#SHA_256},
  {@link EMessageDigestAlgorithm#SHA_384} or
  {@link EMessageDigestAlgorithm#SHA_512}. May not be <code>null</code>.
  @param aHashValue
  The plain hash digest value. May not be <code>null</code>.
  @return this for chaining