Failing tests

Hi Luis,
First of all, thanks for writing this book, I have really enjoyed it.

I have some problems with some tests. (ch06 and ch08).
I see qunitjs 2.x is installed as a dep for qunit 1.x and there are changes on how you call expect (it is assert.expect now).

Also I have a little recommendation on the map of IO monad: just use an arrow function to keep the context of the method.