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 10, Card Hearts 1 ] == 21


score [ Card Clubs 7, Card Diamonds 12 ] == 17


score [ Card Spades 5, Card Diamonds 4, Card Clubs 10, Card Hearts 1 ] == 20