Follow copyright best practices

Hi @lea-33 ,

in #44 we copied a lot of data from zenodo to huggingface. To make this legally fine, we need to follow the [CC-BY license of the zenodo records](https://creativecommons.org/licenses/by/4.0/deed.en). I propose to add a readme file to the huggingface repository (automatically) that contains:
* Links to the original zenodo records
* Authors
* Licenses of the original records. 