faiss 1.6.1 (new formula)

[ankane]

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Adds Faiss, a similarity search library from Facebook

[chenrui333]

Thanks @ankane for your contribution to Homebrew! 🎉 🥇

Without awesome contributors like you, it would be impossible to maintain Homebrew to the high level of quality users have come to expect. Thank you!!!!

[ankane]

Thanks @chenrui333!