document config options
add configuration file and command option parsing
start of MacOS support
Add SMF manifest for illumos and solaris
use duid already stored, if present.
release on shutdown; config section marked by barriers
start to split OS-specific functionality into modules.
some minor tweaks to get things working on smartos, also include lifetimes in RAs
working protocol implementation; with caveats

t1 and t2 are not handled properly in edge cases
retry intervals and limits are not completely according to the spec
we don't handle multiple prefixes at the moment nor do we handle lifetimes
starting to handle message 3 and 4
add encoding and more protocol logic
Add more message types.
Basic packet handling works. Need to add niceties and then all of the handshake logic.