Add finger up/down animation to Net-tac-toe

[paulstraw]

Is your feature request related to a problem? Please describe.
Right now, the hands don't move when A is pressed.

Describe the solution you'd like
The "finger down" state has already been drawn. Both players should see this; probably the easiest way to do that is send A down/up events over the network.

Describe alternatives you've considered
Not animating the hands, which is what I did originally.

Additional context