image.Image output

[kris-watts-gravwell]

The PNG interface automatically creates a PNG. Add an interface that outputs an image.Image interface so we can easily do some resizing and image manipulation afterwords.

use this: https://pkg.go.dev/go.oneofone.dev/resize

That way we can deal with the crappy interpolation implementation in the canvas.Canvas by just making larger images and then scaling them back down using that interface.