+- Apply patch from Cyril Elkaim to fix an issue with MacOS.
+- Apply patch from Geoffrey D. Bennett to fix retry of control packets.
+- Apply patch from Geoffrey D. Bennett to fix handle RADIUS Class attribute.
+- Bump heartbeat version to handle Class entry in session (v6).
+- Re-arrange session struct to remove padding.
+- Update cluster code to handle v6 packets. Drop compatability for pre-v5.