Document database.yml.example options more extensively

[atonkyra]

Current database.yml.example could list more options that user can specify. Right now it's up to Google and right words to get more complex DB configurations in (as in non-ident auth, other server etc...)

I'd propose that at a minimum, database.yml.example should contain these fields (or something similar):

env-keyword:
  <<: *defaults
  database: isk
  # host: localhost
  # username: isk
  # password: changeme