+HS/04 Add support for keep_environment and add_environment options.
+
+JH/43 Tidy coding issues detected by gcc --fsanitize=undefined. Some remain;
+ either intentional arithmetic overflow during PRNG, or testing config-
+ induced overflows.
+
+JH/44 Bug 1800: The combination of a -bhc commandline option and cutthrough
+ delivery resulted in actual delivery. Cancel cutthrough before DATA
+ stage.
+
+JH/45 Fix cutthrough, when connection not opened by verify and target hard-
+ rejects a recipient: pass the reject to the originator.
+