Fewer cards and printlns
Refactor to move loops into a Matrix class. 63% speedup.

This interface is a bit less intuitive for Scorer code, but should allow for
significant savings by more efficient Matrix implementations.

Conflicts:
    src/GameState.java
    src/ScorerTestCase.java
    src/Scorers.java
preserve flushdraw state on copy
Cache OfcCard objects. 5% speedup
Make Matrix cleverer, by sorting ranks. 15% speedup.
Remove OfcHand.copy. 11% speedup. Also fixes an off-by-one error.
Fix another off-by-one.
Use flushdraw skip technique in matrix. 2% speedup.