This commit adds code to the `03_feature_extraction.ipynb` notebook to print time-domain features. The features include mean, max, peak, peak-to-peak, RMS, variance, standard deviation, power, crest factor, form factor, pulse indicator, margin, kurtosis, and skewness. The features are calculated using the `FeatureExtractor` class and displayed in a pandas DataFrame.
Introduce a new testing script that generates mockup data and applies the FeatureExtractor class to calculate and display features. This test script assists in verifying the functionality of the feature extraction methods with controlled input data.