LogHelper rotating file handler

[MattBuckley-TfN]

Add functionality to log_helpers.get_file_handler to allow using RotatingFileHandler or TimedRotatingFileHandler and update LogHelper.add_file_handler default to using a RotatingFileHandler.

Add constants to define the default values for both rotating file handlers:

• RotatingFileHandler defaults:
  • Max size 10MB
  • Backup count 10
• TimedRotatingFileHandler defaults:
  • at time: 00:01
  • when: W0 (monday)