Decided not to support the incremental API, its not necessary as the ergonomics are not that big a deal.
Got operators to pass the sanity base cases, which means now all upfront constructors pass the base cases!
Next up is getting it to pass the array container generation.
Adjusted upfront api a bit, def_using no longer handles the namespace case, a sepearate function: def_using_namespace now does.
Mostly fixes to the seralization as I generate more cases to find the bugs.