Consolidate documentation

[mithro]

There is a lot of documentation scattered through the following pages, it would be good to merge / consolidate them into one location.

• README.md in https://github.com/im-tomu/fomu-hardware repository
• Website at https://fomu.im/ and https://github.com/im-tomu/fomu.im
• Workshop at https://workshop.fomu.im and https://github.com/im-tomu/fomu-workshop
• Toolchain at https://github.com/im-tomu/fomu-toolchain
• Foboot at https://github.com/im-tomu/foboot
• Quick start documentation?

The documentation should cover;

• What Fomu is?
• How to buy a Fomu?
• What Fomu version do I have?
• How to get the toolchain setup and installed
• How to get started with examples.
• How to contribute to the project.