PerMetrics: A Framework of Performance Metrics for Machine Learning Models

• Reformat ClassificationMetric, RegressionMetric, and ClusteringMetric
• Fix bugs in metrics:
  • ROC-AUC score
  • F2 score, FBeta score
  • Hamming Score, Accuracy Score
• Add metrics to ClassificationMetric:
  • Brier Score Loss (BSL)
  • Kullback-Leibler Divergence Loss (KLDL)
  • Cross-Entropy Loss (CEL)
  • Hinge Loss (HL)
• Update docs, examples