Add electricitymaps app to presentation slides

[raar1]

Add it as e.g. an iframe on one of the slides. Also have some screenshots and talking points on the following slide in case the network is bad on the teaching day.

[raar1]

It would be good to demo the application a bit during teaching, to make the course a bit more interactive and stop people falling asleep.

[esclapez]

Yes ! Maybe asking about where and when to run a workflow, as a small live exercise.

[raar1]

This seems to be done.