add option warning to show_empty:

[Mariusthvdb]

show_empty: false hides the card if no entities are showing, which makes sense of course. Still, under certain conditions it would be useful if the card could show a default message like: 'No entities available'.

Right now, without the show_empty: false an empty card is displayed like this:

which is kind of ugly, and useless. Not showing makes the user forget about the card.

so, please consider adding an option for show_empty: warning, and add a configurable warning (maybe even with template...)

thanks!

[Mariusthvdb]

thank you!
happy New Year!