Resetable Worlds

(Note:  I was unsure which Topic this idea should have gone under)

There should be a way to "lock" a world, so when you rejoin it will reset to how it was before, and to lock/unlock a world, you would use (as OP)  /world lock and /world unlock. This would allow for minigames to be reset without the map maker having to create their own map resetting commands/datapack.