Add new options to defaultConfig

[jfischoff]

Should add

              [ ("checkpoint_timeout", "60min")
              , ("max_wal_size", "2GB")
              ]

as well

[parsonsmatt]

I've observed a really large speedup by in our test suite by setting autovacuum = off too, though that's on my local postgres system installation and not with tmp. Like the runtime goes from 12m to 6m.