Documentation Overhaul

[vkorbes]

Here's the initial version of our new docs.

Notes:

• Internal links should all be working, but please do check the external ones.
• The references section hasn't been reviewed, so it's probably out of date. We'll fix it on the next stage.
• Links still need to be added in the example project guides to the actual files where the projects are. Pending Mirror examples to separate repo #128.
• For missing files, TODO stuff that you'd like to note down and so on, please use the Docs Work base in Airtable.

Articles/guides that we probably want but that are still pending:

• A project involving hot reload
• The socks shop project
• Migration guide from Docker Compose to Garden
• Getting started with Kubernetes using the Garden framework
• Contributing to Garden

Closes #274.

[drubin]

I imported this project into a "test" gitbook project to be able to see how it gets formatted.

I think we need to tweak a few things?

https://davidgarden.gitbook.io/allthedocs/v/allthedocs/

cc/ @eysi09 @ellenkorbes