js-on-sx: callable Number/String/Boolean/Array + Array.sort
Builtin constructors now have :__callable__ slot. js-call-plain
and js-function? detect dicts with __callable__ and dispatch
through it. Number('42')===42, String(true)==='true', Boolean(0)
===false, Array(3) builds length-3 list.
Array.prototype.sort(comparator?): bubble sort via js-list-sort-
outer!/-inner!. Default lex order, custom comparator supported.
Wide scoreboard committed: 259/5354 (4.8%) from earlier runtime.
438/440 unit (+11), 148/148 slice unchanged.
giles
1459f7a637