dictionary sorting functions

[tap]

We have feature requests for the ability to sort a dictionary. How might we go about this?

• pass in a patcher (as JSON? as some sort of named reference to a file on disk?) that provides the sorting algorithm
• pass in some other kind of code to be evaluated (js? gen-expr?) as the sorting algorithm
• pass in a dictionary that contains the rules of the sorting -- seems promising, but need to figure out exactly how this would work