Changed

• Upgrade node-gyp from ^3.8.0 to ^4.0.0 (#614) (@ralphtheninja)
• Refactor worker cleanup into BaseWorker::DoFinally() (#617) (@vweevers)

Added

• Clarify expected behavior in iterator-test (31b66cf) (@vweevers)

Fixed

• Prevent segfault: create reference to chained batch object (#621) (@vweevers)
• Skip writing empty (chained) batch and make callbacks asynchronous (#619) (@vweevers)
• Throw error in iterator_seek if iterator has ended (#618) (@vweevers)