Add scripts to set-up virtual environments.

..._tools/HPC_scripts/train_model_era5_container_template.sh

...prediction_tools/HPC_scripts/train_model_era5_template.sh

video_prediction_tools/env_setup/create_env.sh

video_prediction_tools/env_setup/install_venv_container.sh

video_prediction_tools/env_setup/requirements.txt

video_prediction_tools/env_setup/requirements_container.txt