Documentation for example datasets

[VeckoTheGecko]

Is there any documentation about the datasets in examples-data (which are in turn used throughout the parcels examples)? Perhaps it would be worth adding a file examples-data/README.md to add quick descriptions to these. This can be propagated through to users in parcels if we want as well just by linking to the README here on GitHub.

Motivation

parcels_tutorial.ipynb mentions

since we know that the files are in what’s called Parcels FieldSet format, we can call these files using the function FieldSet.from_parcels()

I feel like the following would be better

The "MovingEddies_data" dataset contains data that is in Parcels FieldSet format. We can ingest this data into parcels using FieldSet.from_parcels(). For more information on available datasets see link

[erikvansebille]

Yes, I fully agree! Probably best if I write this README, since I know where the datasets came from. I'll assign to myself