You actually don't have to do this. All saves on PC, Mac and Linux are saved to two locations - one is in the game's "saves" folder and the other is stored in a separate location on your computer. When you load up a new version the game will search for saves in both locations and move them from the external folder into the "saves" folder for you if the "saves" folder is empty :)
In short, on PC, Mac and Linux you just extract the new version to a fresh folder and play!