Function rust_action_heroes::lib::load_sprite_sheet

pub(crate) fn load_sprite_sheet(
    world: &mut World, 
    sprite_img: &str, 
    sprite_key: &str
) -> (Handle<SpriteSheet>, ProgressCounter)

I think this was basically copy-pasted from the Amehtyst docs.

Except the Ametyst docs omit the use of ProgressCounter which I actually like using.

Don't forget to tip your ProgressCounters kids.