Taofold v2.1.1

This update includes the following changes from #363 :

• Fix the reward loop in neurons/validator.py and add error handling.
• Refactor the Protein() class to use absolute paths for file handling.
• Add a new parameter to the run_step() method in folding/validators/forward.py to avoid unnecessary processing done by the validator. Carry over this parameter to neurons/validator.py in the forward() method.
• Decrease the epoch length for weight setting from 300 blocks to 150.
• Maintain the ordering of the events for rewarding in get_energies() from folding/validators/reward.py