Bowling: Implemented neat printing for frame 10

Known bug: The third strike of a frame 10 turkey comes out as '10' rather than 'X'.
Bowling: Fixed bug where a frame 10 turkey would be output as 'X X 10'
Bowling: Fixed bug where the second bonus score for frame 9 was never added when the first roll of frame 10 was a strike
Bowling: Added method to calculate cumulative score at a given frame
Bowling: Fixed bug where printed frame scores were not cumulative