Filled out information in the about pop-up

[darkksuns]

Opening a PR here just to make sure you're all happy with how I've worded the instructions. Added some images to the images folder too of the icons with transparent backgrounds and used them in the explanations too.

Screenshots if you don't want to bother pulling:

[Ciaranengelbrecht]

Awesome looks great to me definitely good to have this merged makes it feel more polished