+ fixed race

This commit turns all dial logs into log.Events.

Everything's great except for one problem:
The LoggableMap I'm using does not print out things
correctly. I gave it peer.IDs, and Multiaddrs
and both got logged as nothing `{}` (didn't even call
their String() methods!) So, for now, this function
encodes it when called... This is wrong and should be
fixed before being merged in. Otherwise we  will be
constantly encoding peer.IDs and Multiaddrs without
needing to.

@briantigerchow how do you suggest doing this?
I don't know my way around your Loggable.

off by one error seeking to end of single block file

AddrSplosion -- Partie Deux Avec Vengeance

Implement io.Seeker on unixio.DAGReader

dropped down log.Errors

misc user-friendliness fixes

CLI changes

NAT-Lite

should be returning false.

Exposing the NAT to the core is unnecessary. The Host can take
care of it. If a need emerges, we can address it then.

- allow retrieving addresses
- allow notifications on mapping changes
- allow lifecycle mgmt (future commit will manage it)