PR #8258 - nx-neptune to run algorithms on Amazon Neptune Analytics

[Andrew Carbonetto]

Dear NX Maintainers,

PR#8258 looking for review: pull#8258.  Doc updates only here!   

As per discussions#6079, I have a PR to add nx-neptune (backend="neptune") as a backend integration to Amazon's Neptune Analytics.  The backend works with a select group of algorithms available in Neptune Analytics. 

You can checkout the latest release of the backend on pypi: https://pypi.org/project/nx-neptune/

Please let me know if you have any questions, and thank you for your time,

Andrew Carbonetto

https://github.com/acarbonetto