Add subtitles

[FD-]

Hi,
It would be great if the library also provided a possibility to add a subtitle to the toolbar. The subtitle would show below the title even in collapsed mode.

This functionality is implemented e.g. in this library (which doesn't support multiline titles).

[johan12345]

Interesting idea! Adding a subtitle would probably be possible, although it would most probably make the code that calculates where the text goes and how it animates even more complicated. As we don't need a subtitle ourselves in our project, we unfortunately don't have the time to implement this. But we would of course accept it if someone sent a Pull request.