Help needed - Custom Key Icons?

[Mrwhitepantz]

Hello there, I'm looking to create an addon that will allow me to change the icons that show up in-game when you can press a key to perform whatever function.

I'm talking about how it shows, say, an E key when you want to confirm deconstructing, or the R key for taking everything in a container. If someone can point me in the right direction that would be awesome. This is my first addon, and I'm trying to make things easier for a friend.