Score the input hand.

Score calculated according to standard blackjack rules. If a hand has an ace that is, when scored as an eleven, causes the hand to exceed 21, the ace is acounted as a one.

score [ Card Spades Ten, Card Hearts Ace ] == 21


score [ Card Clubs Seven, Card Diamonds Queen ] == 17


score [ Card Spades Five, Card Diamonds Four, Card Clubs Ten, Card Hearts Ace ] == 20