Implement new docs explorer

[timsuchanek]

As designed here: https://www.figma.com/file/p8f8MaG7ZRnuCc4lVv7w6t/GraphiQL-2.0?node-id=0%3A1
This will be the last part in our road to v2, as this is the most ambitious component of them all.

Hello, any ways I can help?

[jonathanawesome]

👋 Hey @dlcognite. I've a new discussion here that goes over the current state of this component, very interested in your feedback!