Add Llama2 + EC2 tutorial using Runhouse

[rohinb2]

A simple code file to stand up a Llama2 model on an A10G running in EC2. Uses the Runhouse Python library to easily provision an instance, copy code over, and serve the model.

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• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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Thanks for contributing 🎉!

[rohinb2]

cc: @HamidShojanazeri @mreso

Sorry to tag, not sure who to request for review here.

[dongreenberg]

Also adding in @subramen , with whom we've previously discussed this example.

[HamidShojanazeri]

Thanks @rohinb2 for the PR will sync up with Suraj and review.

[rohinb2]

Hi @HamidShojanazeri, I made a new PR for the new format.