COVIDcast page

[tildechris]

Implement the redesigned COVIDcast page.

The COVIDcast visualization assets should be referred to their published URLs. We can assume that these are hosted on netlify for now.

[sgratzl]

see #27. But we have to decide which version of COVIDCast we wanna integrate, since small adaptations are required. The current linked pull request preview is one based on my uikit adaptations