v0.7.1

@mdapena

Release Note

Refactored the StdOutLogger to improve usability, configuration, and standardization of logging messages.
Enabled a config() method in the StdOutLogger for straightforward configuration of the Pyventus logger.
Introduced a critical() method in both the StdOutLogger and Logger classes for logging critical-level messages.
Updated the error() method in both the StdOutLogger and Logger classes to include the exc_info parameter, allowing exception information to be logged for better insights during debugging.
Enhanced the execute() method of the Event Handler to include exception information in error logs, improving debugging when errors occur.
Improved error logging in the Observable class by including exception information in error logs for better debugging when errors occur.