Make a distinction between Shadowless and First Edition cards

[ghost]

I think it would be nice to somehow make a distinction between first edition cards / shadowless cards of the Base set. Maybe include it as a new set? Or as a property on each card?

[MrRonark]

Other sets also have alternate 'versions' - such as the reverse-holo cards, prerelease editions, etc. This makes it much more complex but a 'card versions' list would be nice :)

[Tommatheussen]

I'll definitely need this for my application, I'm building an electron app to keep track of collected cards.
Basic cards are ok for now, but getting the different versions possible from the API would be great :)