Update first snippet

This is a proof-of-example conversion. One snippet is updated to a suggested new set of metadata fields. The commits are on a new  branch and the pull request is against the `reorganization` branch - not `master`!

The suggested workflow is to create pull requests and discuss them before actually modifying the repository.

The `reorganization` branch has to be kept alive until all snippets have been moved and updated, so I suggest that we carry this on with priority because anything else that is going on on `master` in the meantime will have to be merged later too.