Remasters, Remakes, Reimaginings and HD Rereleases have been going on with increasing frequency for several years now. Sometimes it seems like every other game released for consoles today is an up-port of an earlier game. Nintendo released Super Mario All Stars back in 1993 and it was a collection of the first four Super Mario games, but they were redone in fancy 16 bit graphics and SNES sound. I remember being impressed by this as a kid, and also by the fact that all the games were on one cart.
I think this was the first remaster rerelease of game. There were ports before that, but they weren't rebilled as improved versions of the game. If you put your game on a new system, you took advantage of that systems capabilities, no fuss about it.
Correct me if I'm wrong, but I think this was first game that was put out as a remaster. The term and definition is a little hazey, but I can't think of any earlier games.