* Add auto formatting with black and isort
* Reformat code
* Ignore typing errors
* Add note about line length
* Add minimum version for isort
* Add commit-checks
* Update docker image
* Fixed lost import (during last merge)
* Fix opencv dependency
* Change saving/loading normalization parameters to use single pickle file
* Remove 'use_gae' from RolloutBuffer compute_returns function
* Add some missing tests for normalizer, nan-checker and PPO clip_value_fn argument
* Update changelog
* Fix typo
* Use proper pytest.raises for catching errors in tests
* Add comment on GAE and how to obtain non-GAE behaviour
* Remove save/load_running_average from VecNormalize in favor of load/save
* Update changelog
* Update docstring
* Add accidentally removed tests for VecNormalize
Co-authored-by: Antonin RAFFIN <antonin.raffin@ensta.org>