- package vars for tagged loggers
- weed out spurious fmt.PrintX and log.PrintX logging
- tried to second guess loglevel for some :)

- packages use tagged logger sending log messages to shared (process-wide) logging engine
- log writers (interface ethlog.LogSystem) can be added to the logging engine by wrappers/guis/clients
- shared logging engine dispatching to multiple log systems
- log level can be set separately per log system
- async logging thread: logging IO does not block main thread
- log messages are synchronously stringified to avoid incorrectly logging of changed states
- README.md
- loggers_test

Updating the state /after/ the entire transition creates invalid
receipts.

Reworked peers to check for public key duplication and adding peers to peerlist only after the handshake has come in

* You'll only ever need to update the state by calling Update. Update
  will take care of the updating of it's child state objects.