PyBullet Envs compatible with Gymnasium

Install with pip via PyPi: pip install pybullet_envs_gymnasium

Locally (dev version): pip install -e .

Original repo: https://github.com/bulletphysics/bullet3/tree/master/examples/pybullet/gym/pybullet_envs

Note: a lot of things were removed, only the locomotion envs were kept for now.