Better formatting for the parsers.

[WilliamDue]

Currently the parsers have huge tables that are unreadable that makes my emacs lag so some line limit should be made.
The generated code should also be better formatted such that the indentation and spacing is more uniform.
Also ideally if futharks algebraic data types could be used instead of unsigned integers then the parsers would be more human readable.

[athas]

I caution against using sum types. The type checker is not well tuned when there are many constructors, and the type errors would be unreadable.

[WilliamDue]

Hm maybe the solution is to just make a comment in the resulting parser with what terminals and nonterminals correspond to.