* fix num_envs=test_num * fix mypy
- A DummyTqdm class added to utils: it replicates the interface used by trainers, but does not show the progress bar; - Added a show_progress argument to the base trainer: when show_progress == True, dummy_tqdm is used in place of tqdm.
- add VectorEnvWrapper and VectorEnvNormObs - obs_rms store in policy save/load - align mujoco scripts with atari: obs_norm, envpool, wandb and README