Fixed end-state handler to stop taking Ball messages when end-state
detected. Looking at Yahoo's results board, failing at this could
result in the system looking as if I had poor win-state detection.
Fixed win-state detection to enclose the card matrix. This makes the
coordinate tests look like it takes coordinate pairs, which is the
effect we want, improves readability, and reduces errors.
them a consistent meaning.
Changed the 'BINGO' algorithm to use just numeric coordinates, converting
exactly once from the BINGO to 0..4.
Changed the test-if-won algorithm to create scoped tests with consistent
signatures. This let me catch an error I missed with the first pass.