Desugaring functions are all done! But we're not ready for the CF backends yet because desugared structures still need to be stashed in the parser.

Expanded vtable for methods to determine whether a combinator is ok to use with regular or CF grammars.

Benchmark is actually broken right now, for mysterious double-free related reasons. I will dig into this tomorrow.

counted_array now holds parsed_token_t's. TQ will fix the problem with accumulate_size. Compile-time bounds checks added to int_range.