Add ability to add subcards to non popup cards like Button cards.

[BacchusIX]

I love how you are able to add cards to the Popup card and wish this was an option on the other cards. OR possibly and easier route, create a "header" card that essentially has the same functionality as the pop-up card just without the pop-up function.

Sometimes it would be nice to be able to create a single, large in the bubble style than multiple smaller ones.

thanks