Since the application does not use a database, it's confusing to have to
set a bogus database URL environment variable. This change follows [the
Lucky guide][1] suggestion for disabling the need for database
configuration. That makes the setup a little easier.
[1]:
https://www.luckyframework.org/guides/database/intro-to-avram-and-orms
The most common is "How do I set my custom domain" (answer: APP_DOMAIN)
but this also requires setting LUCKY_ENV=production which requires
SECRET_KEY_BASE, DATABASE_URL, and PORT
The basic idea here is to fetch the post with the medium API, parse the
JSON into types, and then re-display the content. We also have to fetch
each media object as a REST call to get things like embeded iframes.
