Add lightning data from new MTG Lightning Imager satellite

[valkoe]

Now data is available from the new ESA satellite, and it would be great if it could be added as a layer to windy. Especially for areas where the current lightning data does not have coverage (Africa+), this would be very useful addition for following thunderstorms when I'm travelling/working.

Data description: https://user.eumetsat.int/resources/user-guides/mtg-data-access-guide
Example accessing data: https://github.com/diegormsouza/spaceweek2023/blob/main/colab/MTG_LI_EUMDAC_Example.ipynb