def log(message, severity = DEFAULT_SEVERITY)
      fail 'Logfile not registered' unless @registered
      return if message.nil?
      @logger.add(severity, message, @name) if should_log?(severity)
    end
def log(message, severity = DEFAULT_SEVERITY)
      fail 'Logfile not registered' unless @registered
      return if message.nil?
      @logger.add(severity, message, @name) if should_log?(severity)
    end
Log a message to the configured logger using the severity and program name
 as specified
 @param [String] message message to be logged
 @param [Number] severity message's severity
 @see http://ruby-doc.org/stdlib-2.2.4/libdoc/logger/rdoc/Logger.html
 @private