only build on node 6
only build on node 6

NickCarneiro/curlconverter,NickCarneiro/curlconverter,NickCarneiro/curlconverter,NickCarneiro/curlconverter,NickCarneiro/curlconverter,NickCarneiro/curlconverter,NickCarneiro/curlconverter,NickCarneiro/curlconverter,NickCarneiro/curlconverter