Sack to hold the Presents

[vgmoose]

A Sack object should be created to house presents that a Player picks up.

It should have the following:

• Max value of presents it can hold (int)
• ArrayList of Present objects on the sack
• Current value of presents in the sack (length of array)

In addition to this, there should be helper methods like so:

• add Present to Sack
• remove x Presents from Sack (and return the sub-ArrayList of them (this is for when a Player gets hit by an enemy, the x Presents removed can be random))

You should also see about adding a Sack field variable to the Player object (so a Player can have their own Sack)

[vgmoose]

More specifically:

• the Sack should check if it's filled before allowing more Presents to be added
• in addition to remove(x), there should be a clear() method to remove all Presents at once
• a boolean will need to be added to keep track of which mode the Sack is in (weight or quantity)