helper.config updates

- Assign default values by default and override with loaded values
- Display a more user friendly error message when the configuration file can not be parsed
Exit with 1 if the loading the config raises a ValueError
Add the NullHandler to the root logger
helper.unix fixes

- Use the pidfile from the config file if specified
- Add a NullHandler to the LOGGER to avoid a warning message if no logger is configured
- Remove debug log file
Update version and version history