Updates for Second Edition

[davegurnell]

This is an aggregator thread to track planned updates for a second edition of the book. High level planning should go here, and individual updates should be tracked in their own issues.

In preliminary discussions, @noelwelsh, @arosien and I have discussed a few things we'd like to do:

1. Change the build system to mdoc

2. Update to Cats 2.0

3. Discuss Parallel and modify our discussion of Validated accordingly. I tend to stick to Either all the time these days, using parMapN, parTraverse, and so on to do parallel combination.

4. Add introductory content on Cats Effect. Possibly just a discussion of the basic type classes and IO. Other books/material can use this as a starting point to bridge further into, FS2, Monix, HTTP4s, and so on.

Is this a complete list? Is there anything else we want to cover?

[noelwelsh]

I'm currently working on the conversion to mdoc. I think we should consider creating a separate web site for the book now that Inner Product is getting involved.

[noelwelsh]

My current progress is on feature/mdoc.

[arosien]

I have started a cats-effect version of the exercise solutions.

[noelwelsh]

feature/mdoc is merged.