* Pin ember-changeset-validations and its dependencies to 3.9
Future versions produce a 'validator is not a function' error
* yarn upgrade
* Upgrade the majority of user facing deps that don't required add. change
not upgraded here due to more changes required:
- ember-page-title
- ember-href-to
* Upgrade ember-page-title which no longer requires ember-cli-head
* Upgrade some devtools related dependencies
* Upgrade some non ember-core test utils
* Upgrade js-yaml which required safeLoad > load
* Upgrade some compilation utils
* Yarn install from workspace root
* Add Python-2.0 to compliance checker
This PR removes storybook and adds docfy and uses docfy to render our existing README files.
This now means we can keep adding README documentation without committing any specific format or framework. If we eventually move to storybook then fine, or if we just want to remove docfy for whatever reason then fine - we will still have a full set of README files viewable via GitHub.