MTL Release (Part 6)

Today, I was happy to see a post on /r/haskell linking to draft documentation about migrating to mtl-2.3.x! There is an mtl-2.3.1 release prep pull request open, so I am hopeful that it will be released soon and I will finally be able to use current versions of the transformers library. I still have a sheet of paper with my TODO matrix stuck to my whiteboard with a magnet!