Update ch04.md

Update with the latest exercise structure.

fix: return traverse of Right in appendix

Fix typo

fix typo

Fix firstWords composition

Monoids

Fix compose type signature

ch03.md: update ringer to wringer

Ch05: Updates reverse example to use newer array syntax

Fix minor typo with comma

Fix a typo in A Spot of Theory example

fix: use concat instead of append

ch08.md example fix

Typo: ringer -> wringer

Fix pureLog in support.js to match the implemenation in the book

The correct turn of phrase is `"put X through the wringer"` - https://grammarist.com/usage/put-though-the-wringer-vs-put-through-the-ringer/

Added missing link to append

fix(ch05): hint change

- replace `flip` with `append`

Ch08: fix findParam to make usage of Maybe reasonable

Fix ch07

Words in the example are appended, not prepended.

https://codesandbox.io/embed/confident-oskar-i4pmi

At line 315, the `fortune` function was defined using `append`, which is not compatible with the expected behavior.
This PR suggests the usage of `concat` instead of `append`, so the output of the `fortune` function would be the expected one.

The expression is "through the wringer" - https://grammarist.com/usage/put-though-the-wringer-vs-put-through-the-ringer/

* reword discussion of how pure functions preserve referential transparency

* typo: bevhavior --> behavior