Monads (and reorganize)

Monads

Finally, monads! Still could use more documentation, but they're here and they work 😄

[1, 2, 3] >>> fn x ->
  [x + 1] >>> fn y ->
    [y * x, y * 10, x - 1]
  end
end
#=> [2, 20, 0, 6, 30, 1, 12, 40, 2]

[1, 2, 3]
>>> fn x -> [x + 1] end
>>> fn y -> [y * 10, y - 1] end
#=> [20, 1, 30, 2, 40, 3]

Of course they work on things other than lists. I'll will be moving the ADT-specifc implementations to Algae, so if you want Maybe, Either, and friends, please use it in conjunction with that library.

Major Reorganization

Still a bunch more to do, but this is already much better. Merging to master, and will continue to tighten stuff up and work through the roadmap.