Animation improved and bug fixed...

1. Fix the previous animation bug, now the piece in the destination cell
won't changed before the piece completed the animation.
2. Both of the player should now able to see the animation of another
player's move.
3. Shorten the animation duration.

Please noticed that the animation somehow can not be performed (or just
can't see) in the GWT amulator (V3 and V4, though V2 works
perfectly...). The angularJS amulator is OK.

The V2.0.1 url:
http://2-0-1-dot-banqi-smg.appspot.com/