Hello,

I'm currently working on a project where I have an amount of text that is slightly longer than my display. For this, I was planning to implement a custom "peek" scroll mode which scrolls back and forth just enough to show the content of the line.

Upon looking at the code, it looks like this would require a commit to SmartMatrix to add support, as there isn't currently a mechanism to supply a custom implementation. I'd like to help and am willing to submit patches, would the maintainers accept patches for one of the below? Which is preferred?

1. Adding a new scroll mode directly to the enum and implement in LayerScrolling_impl.h
2. Adding a new ScrollMode class with the appropriate hooks, and add my own scroll mode there
3. Same as 2. but with additional refactoring to change the existing ScrollMode implementations to classes as well.

Thanks for the support and the excellent library!