sync with the latest kame tree.
clarify command line parser. add -I option. (sync with recent KAME)
rip6query: RIPng query (similar to ripquery) NOTE: we usually do not run route6d on end nodes at startup (rtsol should do the trick). So I figured that route6d can be in /usr/sbin, not in /sbin (routed is in /sbin). Correct me if I'm wrong.