Added grid search for best nis params

[alexpetersburg]

• Run nis_grid_search.py with Base configuration file path, Standalone.bat file path and Ground truth image path
• The script will iterate over all combinations of parameters from GRID_PARAMS and save the result in the grid_search folder,
• grid_search folder contain subfolders named {ssim_metric}_{date}
• Each subfolder contains params.json with gird parameters and NUM_FRAMES images saved every SAVE_INTERVAL