Some tests have been updated, while other which are still a work in
progress have been marked with @pytest.mark.skip(reason="Test need to be updated")

[data.image_utils.py] replaced load_pil_baw by load_pil_grayscale. Updated the docstring and call in the rest of the package accordingly

[models.transforms] Implement RGB and Grayscale transforms, and hook those into our models (closes #15)

[data.augmentations] Move transforms to augmentations; Implement auto-parellisation for ElasticDeformation (partial affects #5); Reflect changes in all relevant submodules

[data.datamodule] Fixes cached dataset model transform application; Improves logging and documentation; Estimate loaded sample sizes and RAM occupance

[data.datamodule] Double-check model_transforms are set before datasets are instantiated; Remove model_transforms from constructor (non-sensical); Improve documentation on model-transforms

[data.montgomery/shenzhen.loader] Simplify loaders, adjust some variable names, comments and add some (commented out) test code to visualize generated images