Add links to sections

[brunosan]

Needs to add an anchor offset to use the ids, and make sure the data space referenced in the link is loaded (e.g. #goal-3 needs goals loaded and in the DOM).

[brunosan]

After https://github.com/SDG-data/web/blob/viz-list/assets/data-loader.js#L32-L34 it's just matter of adding the target link in the append function (and change them to a, not lis).