Refactoring.

Modified the flush-p function. It was the only one calling high-card and
since that seemed a bit unneccessary and stupid I got rid of that function
and replaced it with a function called scores which basically just sorts
the hand according to score.
Refactoring.

Removed the function same-suit-p. It was only called from flush-p
and since flush-p was basically only a call to that function it
seems like a much better idea to just move the code.