Split data and LXCat references in terms of use

[daanboer]

In GitLab by @daanboer on Mar 23, 2023, 15:33

The terms of use present all references relevant to the currently selected data, e.g. the references related to the data, and the references related to LXCat itself. However, these references are presented in the same table, making it quite confusing which references are related to the data, and which are related to the platform. Splitting these references into separate tables will allow the user to distinguish them more clearly.