registered new Corona infections at [1]. ./update.sh crawls this and appends
the day's data as a single line to ./daily_infections_table.txt, then calls
./enhance_table.py which outputs an enhanced version of the data to
-/var/www/html/berlin_corona.txt/.html, which is served by my web server at [2].
+/var/www/html/berlin_corona.{txt|html}, which is served by my web server at [2].
A systemd timer whose files are provided as ./berlin-corona-table.service and
./berlin-corona-table.timer calls ./update.sh once per day, when the new daily
data are expected to be found at [1].