Contact Experiment Completed, Early Stopping, Evaluation Code for Classification

[DanielChaseButterfield]

Features

• Contact Experiment Completed (and ablation study), with paper directory with model names (and links to weights).
• Added Early Stopping to replicate the Early Stopping mechanism from MorphoSymm.
• Test cases for the HGNN Classification models to make sure they return the same result as the training function.

Refactor

• Updated the README.md with updated information.
• Evaluation code for HGNN Classification now returns 16 class labels and predictions.

Deletions

• Regression models are not confirmed to be working as of right now.
• MLP models are not confirmed to be working as of right now.
• Removed test cases that involved the regression models and MLP models, as the evaluation code isn't curently working.