This will enable us to access the auth records, which we store in a separate database for weird legacy reasons!
We don't do anything else yet, just set up the connection to be available.
(NOTE: This commit was a bit of a history rewrite: we started working on this with `database.yml` still gitignored, but then in 8fb6e82 we added it back in to be able to fix a bug in 44c42f9. So previously this branch added back `database.yml` to git *and* added `openneo_id` to it, but since then I've rebased against the other changes, and rewrote history to make this a change to *just* add the database! I also moved it in the timeline, to be before some of the other things that depend on it.)
Without this, searches for negative of `fits` or `species` would crash, bc somewhere Rails set the default SQL mode to be stricter than before. This just sets it back!
We gitignored it a long time ago as the way to hide our db secrets, but that's not how we manage them anymore! (Or, well, we haven't done production deployment with this new setup yet, but you get the point.)
This helps clarify what the database config oughta look like!
