+PP/02 DANE: add dane_require_tls_ciphers SMTP Transport option; if unset,
+ tls_require_ciphers is used as before.
+
+JH/34 Re-introduce enforcement of no cutthrough delivery on transports having
+ transport-filters or DKIM-signing. The restriction was lost in the
+ consolidation of verify-callout and delivery SMTP handling.
+ Extend the restriction to also cover ARC-signing.
+