will have an easier time replacing it with something different, even if
it is a second radix-trie implementation.
sys/net/route.c and sys/net/rtsock.c no longer operate directly on
radix_nodes or radix_node_heads.
Hopefully this will reduce the temptation to implement multipath or
source-based routing using grotty hacks to the grotty old radix-trie
code, too. :-)
* fix crash when cluster was involved
* extension offset is constant
* fix endianess issues in BoS loop
* free cluster if INET not defined but icmp_respond sysctl != 1