Returns a sorted copy of a deque.
ordf must be a function which can accept any two elements from
deq as arguments.
It must return one of the symbols
> to represent the relative ordering of
those two elements.
The comparison function defaults to the built-in function
ord. Custom comparison
functions will have significantly worse performance.
(let sorted (sort "Hello, world!")) (prn sorted) ; prints !,Hdellloorw