Improving Dice calls in Board API

Made the following improvements:
- Board View
    - all dice related methods in the Board View now start with `dice`
    - all dice methods now take an int representing the dice to change as their first parameter
    - unit testing for all dice methods
- Level One Activity
    - `onClick` now calls `rollDiceAction` instead of having its code in the menu area
    - `Random r` is now a class level variable so it isn't initiated for every click
    - created function `rollDice` so that the range doesn't have to be typed again
    - starting to add variables to represent game state