[Feature Request] Update font without clicking enter

It would be cool if the program updated the font on the font preview window as you scrolled, without having to click the enter key

[sdushantha]

This would be possible if we can implement #23

I was thinking that we could use fzf's preview window to display the font preview image. This means users wont have to press [ENTER], to view the font preview because fzf automatically displays the content in the preview window just by highlighting it.

[sdushantha]

@hibatica You might like fontpreview-ueberzug by @OliverLew. That version updates the font without having to clicking enter.

I think this could be done with my version as well, but I'll have to go through fontpreview-ueberzug's code to see how its done.