[ref #159] Update the game only if the setup is unchanged after a fixed time period

This should mitigate problems with detecting wrong stones (for example on a human hand) while playing a move.
[ref #159] Reduced the time period the setup has to be stable to 100ms. Tested it and seems to work perfectly with that value.
Update comment
Merge pull request #161 from augmented-go/robust_game_update

Robust game update