Implement better Undo functionality

[Sebmono]

The current implementation of Undo is very frustrating and inconsistent. Some examples off the top of my head:

• Can't undo the selection of a technology action or researh, even if no new information has been revealed. This can be very problematic if you didn't notice a perquisite on a tech or only realize after the fact a subtle nuance in card wording (like upgrade 2 ships by one which means you can't select the same ship twice, e.g.)

• Can't undo production choice

Generally speaking, we should be able to undo all the way back to the beginning of our player turn, as long as new information hasn't been revealed (like a tech research event) or another player hasn't had to make a decision.

Thanks for the overall module, but would love to see the many cases removed where we get locked into terrible decisions that in real life we would just change at the table.

[Jabub]

I just want to chime in to show support. In my last two games, we've encountered a couple of bugs that threaten to lock the game (and one time it actually did). Each time an improved undo function would have helped immensely, allowing us to do different moves and avoiding the bugs.

(the bugs specific bugs have been reported)