def logger
      @logger ||= ADAL::Logger.new(Logging.log_output, Logging.correlation_id)
      @logger.level = Logging.log_level || DEFAULT_LOG_LEVEL
      @logger
    end
def logger
      @logger ||= ADAL::Logger.new(Logging.log_output, Logging.correlation_id)
      @logger.level = Logging.log_level || DEFAULT_LOG_LEVEL
      @logger
    end
Creates one ADAL logger per calling class/module with a specified output.
 This is to be used within ADAL. Clients will have no use for it.

 Examples usage:

   require_relative './logging'

   module ADAL
     module SomeModule
       include Logging

       def something_bad
         logger.error('An error message')
       end
     end
  end

 @param output
   STDERR, STDOUT or the file name as a string.