toy stream example
more changes to Brook
Change from Or(lhs, rhs) to Or(es).

This allows us to go from constructions like:

  Or(Or(Or(a, b), c), d)

to:

  Or(List(a, b, c, d))

resemble a "normal" regex.
Adds NDAs, DFAs, minimization, and a bunch of other junk.

This is still really ugly and unformed. But it seems to be working
so far.