Refactoring

[leobel]

Refactor the interaction between the board game view with other.

1. Board view offer an interface to listen for the following events:

   • User touch a ball (onTouchBall(Point p))
   • User touch on an empty cell (onTouchEmptyCell(Point p))

2. Use an interface to define how interact with the board animation and provide all the methods necessary for animate each situation:

   • onSelectBallListener
   • onMoveBallListener
   • onScoreListener
   • onAddBallListener