code: func (l *LogEvent) LevelJustified() (rv string) {
  	rv = l.Level.String()
  	if len(rv) < 5 {
  		rv += strings.Repeat(" ", 5-len(rv))
  	}
  	return rv
  }
docs: // LevelJustified returns the log level in string form justified so that all
  // log levels take the same text width.