[Bug-gnubg] FEATURE SUGGESTION: Use arrows to skip through move list

[Ian Shaw]

I thin it would be cool if we could use the arrow keys to step through a
game:

Left and Right arrows: Move to next move or cube action for either
player.

Up & Down Arrows: Step to the next move for the player currently
selected.

The idea of the up/down arrows is that you can quickly run through your
own moves, skipping your opponents.

-- Ian