Make API publicly accessible for reading non-user data

[Mr0grog]

We’ve wanted to make the API publicly accessible in some form for a while (in contrast to how we started out; explicitly not wanting that because people were publishing problematic quick-trigger stories and tweets about transient changes or server bugs in the sites we monitor as if they were malicious). As part of my stepping away from the project and putting active maintenance to rest, I’d like to follow through on open API access.

The real barrier here for the past couple years has been the amount of data we’ve accumulated and the free-form nature of the API — it’s easy to issue queries that the DB has to chew on for a long time, and we can’t afford that with open access. Non-essential parameters that take things off the optimal path need to be removed and essential ones need to have restricted, non-public access.

• [x] Make pagination fast on versions (#579)
• [x] Add env/config variable to turn on/off public read access
• [x] #1070
  • Remove non-essential ones
  • Restrict access to essential ones
• [x] Turn on public read access in production

[Mr0grog]

This is now done and deployed (both staging and production)! The UI also has public access in staging (https://github.com/edgi-govdata-archiving/web-monitoring-ui/pull/1037) but not yet in production.