Nano-cat

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* Finalize the introduction of a new CAT template system (``WorkFlow()``).
* WiP: Implement an acitvation strain workflow with custom MATCH-based
forcefields in Nano-CAT_.

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* Updated Nano-CAT to 0.2.4: https://github.com/nlesc-nano/nano-CAT/pull/20.
* Updated Data-CAT to 0.1.5: https://github.com/nlesc-nano/data-CAT/pull/17.
* Import assertions from AssertionLib_ rather than CAT_.
* Simplified to ``AsArray()`` context manager.
* Added the ``["keep_files"]`` option for quantum dot optimizations.
* Removed ``CRSJob()`` and ``CRSResults()``; import them from PLAMS_ instead.
* WiP: Introduction of a new CAT template system (``WorkFlow()``).

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* Moved the ligand bulkiness workflow from the `ligand` to the `qd` block
in the CAT input. See `nano-CAT`_ 0.2.3.
* Updated the formula for the ligand bulkiness calculation.
See `nano-CAT`_ 0.2.3.

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* Fixed a bug where hypervalent atoms where assigned incorrect atomic charges.

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* Added multiple improvements (and bug fixes) to the
ligand conformation optimizer.
* Added a context manager for the `plams.Molecule.as_array()` method.
* Added an optimizer for the ligand vector.
* Updated the ligand bulkiness workflow in `nano-CAT`_ 0.2.2.

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* Added a workflow for calculating ligand bulkiness in `nano-CAT`_ 0.2.1.