* Add environment wrapper for the skrl RL library
* Add training workflow for the skrl RL library
* Add training configuration .yaml files for the skrl RL library
* Add evaluation workflow for the skrl RL library
* Add skrl to RL extra dependencies
* Increase MINOR version and update CHANGELOG
* Add skrl LICENSE to docs dependencies

* adds sensor docs
* adds docs for array ops
* fixes docs about the device used for camera

* implements unprojection operations in torch
* adds GPU backend support in play_camera.py
* adds play-camera to docs
* adds utilities methods to convert any array type to different backends
* adds utilities to convert arrays/tensors in a nested dictionary to a specified backend
* updates changelog and extension.toml
Co-authored-by: Mayank Mittal <mittalma@leggedrobotics.com>

* Fix on physical material initialization
* Updates changelog and extension.toml
Co-authored-by: Kaixian Qu <kaixqu@leggedrobotics.com>
Co-authored-by: Mayank Mittal <mittalma@leggedrobotics.com>