Changed: updated required node.js version to >=8.0
Changed: queryAsync now returns the whole result object instead of just the rows; queryRowsAsync remains unchanged
and should be used when only the result rows are wanted
Removed: createUpsertCTE, as the ON CONFLICT syntax has been present in PostgreSQL for several versions now and it's
clearer than using a CTE, so there's little incentive to keep the old query builder around
Removed: custom query object keys as no need for these had come up