Clean up pseudocode to match planned syntax for the type- and memory-safe
level-2 Mu language.
http://akkartik.name/post/mu-2019-2 is already out of date.
This undoes 5672 in favor of a new plan:
Layers 000 - 099 are for running without syntax sugar. We use them for
building syntax-sugar passes.
Layers 100 and up are for running with all syntax sugar.
The layers are arranged in approximate order so more phases rely on earlier
layers than later ones.
I plan to not use intermediate syntax sugar (just sigils without calls,
or sigils and calls without braces) anywhere except in the specific passes
implementing them.
Snapshot of mulisp before we put it on the back-burner. It's going to take
too long, and we're better off building out the lower layers that make
it more convenient to create.
Kartik Agaram