Document line chart and word cloud

[peterdesmet]

Document charts in such a way that it would be understandable for someone to adapt to JS code.

• [ ] Document main line chart
• [ ] Document sub line chart
• [ ] Document triggers and interactivity
• [ ] Document word cloud
• [ ] Document which libraries are used

[peterdesmet]

Code is somewhat documented: https://github.com/Datafable/epu-index/blob/master/frontend/js/app.js and I assume extensive documentation is no longer required.