Introducing the home-assistant/architecture repo about architecture

[tinloaf]

Should discussion happen in Issues, or should we write up a short description of what we propose (e.g., as a Markdown file) and create a PR as basis for the discussion?

I think the latter would have the advantage that over time, the documentation in the files in this repo can also serve as a knowledge base for developers.

[balloob]

Any knowledge should end up on the developer website. This should just be for discussion. For bigger topics, like UI schema, I can create a new repo.