Suggestion - Update of read me file for sensors

[BBE-FR]

This suggestion could be tagged "documentation"...

This wonderful "BETA" integration have evolved in the last few monthes.

It would be great to reflect all the work performed in the various sensors in the readme file (and prepare the next phase after the BETA...).

More specificaly, while there is a nice table list with all the sensors, the various attributes of each sensor are not described. It would be great to have for each sensor:

• at least a simple list of all attributes (maybe with a description of the behaviour if needed).
• a simple card showing all atributes would be a nice addon (for example a simple entity or markdown card, without any fancy cardmod or theme).

Thanks again for all the work done !

[BBE-FR]

Many can already been done by looking to the following file: https://github.com/delphiki/hass-pronote/blob/main/custom_components/pronote/pronote_formatter.py

And of course it is very helpfull to look at the development console to have the structure of the available data.