Add CopulaABC version from Xuhui into zoo

[xuhuifan]

Summary:

Hi Henri,

Thanks for your suggestion. I've put the related two docs in here. Please let me know if there is better places. Also, I will keep improving the code quality.

Thanks,
Xuhui

Intended Effect:

How to Verify:

Side Effects:

Successful inference in current Notebook examples:

Documentation:

Reviewer Suggestions:

Copyright and Licensing

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• Code: BSD3 (https://opensource.org/licenses/BSD-3-Clause)
• Documentation: CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)