Move quotes to a database

[simonpweller]

At some point, I would like to shift the quotes to a database. That would make it easier to add quotes and we could add endpoints to do this via the API. It would be a good opportunity for contributors to experiment with database technologies and authentication.

Down the line we could even build a simple admin interface for approving quote submissions, editing and deleting quotes, etc.

I want to keep it easy to run the repo locally, so ideally we'd keep a few quotes in memory for local development.

This will need some fleshing out - just capturing the idea for now and opening it up for comments.