+1840. [bug] fdupont
+ Fixed the inheritance of the triple min-valid-lifetime,
+ valid-lifetime and max-valid-lifetime parameters from
+ the global scope, and fixed it for preferred-lifetime too.
+ Added a sanity check refusing incorrect settings, e.g.
+ the lifetime not being between min and max values.
+ (Gitlab #1456)
+
1839. [bug] tmark
kea-dhcp4 and kea-dhcp6 now calculate the DDNS TTL value
based on RFC 4702, Section 5 which suggests that the