We need: - a page for users to view, download, and share the generated group photo (show a `<Warning />` message when it isn't ready yet). - a simple alert at /home to show users when the group photo is ready. It would be nice for the photo to be zoomable like with: https://openseadragon.github.io/  
We need:
<Warning />message when it isn't ready yet).It would be nice for the photo to be zoomable like with: https://openseadragon.github.io/