Changes:
* Added extra JSON parsing input checks.
* Cleaned up Python examples.
* Added Jupyter notebook examples.
* Renamed hyperrectangle conditions with hyperrectangle_csr ([35](https://github.com/xcsf-dev/xcsf/pull/35))
* Added unordered-bound hyperrectangle conditions with hyperrectangle_ubr ([35](https://github.com/xcsf-dev/xcsf/pull/35))