Update Readme, cleanup at the end of runs, RES-2344, RES-2342, RES-2334

[benja-matic]

• Removed table from readme, created a results directory with tables and documentation
• Stripped down results table to exclude old runs and runs that had bugs
• Added code to rm checkpoints and unnecessary directories at the end of training
• This (tentatively) solved ray issue by removing files taking up excess space
• Moved hyperparameter storage to yaml instead of pickle for transparency
• Removed ray.init() and ray.shutdown() in run.py, which were causing problems and providing no obvious benefit
• Cleaned up finetuning and trifecta configs
• Added steps to ensure nans don't get added to hyperparameters due to joining dataframes with different columns