Switching Datasets to Submodule

What does this merge request do and why?

In line with #44 we are moving datasets to a private repository so that they are not exposed publicly. This private repository will then be submoduled into the ELI5 project (The future home of all evaluation efforts)

How to set up and validate locally

• Follow the standard setup procedure for ELI5
• If running make dataset-init is not specified in this documentation please flag that on this MR before running said command

Merge request checklist

• Tests added for new functionality. If not, please raise an issue to follow up.
• Documentation added/updated, if needed.

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