Back and Forward

Implement control that allows you to look at the previous game you loaded or, if you have already backed up, the next one.
The list grows without end unlike the forward and back browser buttons.  If you back up and then go forward, it does not remove your prior forward items.  That is, if I get item1 and them item2, thenI back up to item1, and then get item3, forward will still be possible and will go to item2.