#225 enable logging to different streams

1st step for #225 enable logging to different streams. The next step is to support application history based on this work.

Please first review this work.

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You can add the log in receiveHandler

Like this:
  def receiveHandler = {
LOG.info("Master is now running...")
masterHAMsgHandler orElse clientMsgHandler orElse appMasterMessage orElse selfMsgHandler orElse appDataStoreService orElse terminationWatch
}