Consistent Ordering of Builtins and Libraries

[peblair]

Right now, the order of the entries on the Builtins and Libraries page (horizon link) makes sense to us as Pyret compiler developers, but it seems counterintuitive. They should be reorganized to either (a) be alphabetized or (b) be partitioned into logical groups which are then individually alphabetized. Regardless, we should pick a convention and stick with it.

Note that even in the case of (a), the Builtins should be kept at the top, with the Libraries beneath them.

@jpolitz @shriram @blerner @anyotherhigherpowersthatbe