Improved changelog and release notes, human readable updates

** Which Category is your question related to? **

General, changelog.

** What AWS Services are you utilizing? **

Amplify.

In #2080 I raised concerns with the stability and maturity of the Amplify platform, and the quality of releases. One point was that changelogs are hard to keep up with, partly because changes happen across multiple repositories and partly because the changelog for Amplify CLI is sometimes not updated at the time of the release.

Promises were made to make it easier for developers who depend on this platform to be able to have a more clear changelog, so it's possible to keep track of what may have broken, as for me almost every release broke something.

Well, it seems those promises were empty and updating the changelog went from sparse, to completely not happening. Looking at the "main" [changelog](https://github.com/aws-amplify/amplify-cli/blob/master/packages/amplify-cli/CHANGELOG.md) linked in #2080 the latest version mentioned in the changelog is 3.0.0. Since then, I believe 12-13 releases have happened.

Due to my bad history of updating with breaking changes that took cost heavily on productivity in my small team, I decided to stop updating regularly unless something was broken or if there was a feature out that we really needed. It's now been a month and we are on 3.0.0 still and the first sensible thing is to read the changelog to get up to speed on potentially breaking changes in relation to our platform and the features we use, but there's nothing to read in relation to the CLI?!? I mean, it cannot be anything has been changed on the CLI?

**Is this serious?**

Yes, I am aware that I can scout all 10+ related repositories and read those changelogs, and I do intend to do so, but you said back then, that you would work to aggregate this better to make it easier to keep an overview.