Add "updated at" information

[johnjohndoe]

Please make transparent when the data used in the visualization has been updated. A link to the source might be helpful, too. I think it would be suitable to place the date at the bottom of the page as indicated in the following screenshot.

Implementation thoughts

I already had a look at the code and saw that you exclude the water quality data (data/all.json) from version control. I saw you have a shell script to download the data. Is there a cron job running on the server to regularly fetch updated data? If so, would it be possible to update a time stamp as well?

The other option I see is to read the "Aktualisiert:" field (shown in the following screenshot) from the data source and update the website accordingly if it changes.