# Description

This PR adds the following managers similar to how we currently handle
observation and reward terms.

* **Termination Manager**: Iterates over all the configured terms and
computes the done signals as an OR operator over each term's output.
Additionally, `time_outs` are handled separately as they are optional
(i.e. only used in fixed-length episodic learning).
* **Randomization Manager**: Handles various randomization (such as
resetting the state of the environments, and modifying various physics
attributes).
* **Curriculum Manager**: Iterates over all the configured terms and
sets the curriculum setting into the environment accordingly.

## Type of change

- New feature (non-breaking change which adds functionality)
- This change requires a documentation update

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./orbit.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [x] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file

---------
Co-authored-by: David Hoeller <dhoeller@ethz.ch>
Co-authored-by: Nikita Rudin <nrudin@nvidia.com>