stineje/CharLib

AI Summary: Implement a feature in the CharLib open-source standard cell library characterizer to automatically infer input and output pins from cell functions, eliminating the need for manual specification in the configuration files. This involves modifying the existing `cell` configuration structure to make `inputs` and `outputs` optional and adding logic to parse function definitions to identify I/O pins.

AI Summary: Implement a logging system using Python's `logging` library to replace the current `print` statements in the CharLib standard cell library characterizer. The new system should provide five logging levels (DEBUG, INFO, WARNING, ERROR, FATAL) with configurable error thresholds to control program termination behavior. The goal is to improve error handling and user messaging clarity.