Add elm-review to elm-book

[henriquecbuss]

What we have
We have a really nice elm-review config in our app. However, we're not using that config on our elm-book

Proposal
Use the same review config (or at least a similar one) on elm-book. We should also run it on our CI

Why
Because elm-review is awesome, and we should use it

How
If elm-review supports it, we could just use the same config, but point at a different elm project. Otherwise, maybe we could use UNIX symbolic links (we already do this for some files on elm-book)

Additional context
Discovered we're not running elm-review on elm-book during #805