instructions for the AWS Marketplace (#2135)
instructions for the AWS Marketplace (#2135)

also added instructions to download additional notebooks into the work directory
i8run/BigDL-1,wzhongyuan/BigDL,i8run/BigDL-1,i8run/BigDL-1,wzhongyuan/BigDL,yiheng/BigDL,zhangxiaoli73/BigDL,yiheng/BigDL,zhangxiaoli73/BigDL,qiuxin2012/BigDL,zhangxiaoli73/BigDL,wzhongyuan/BigDL,qiuxin2012/BigDL,yiheng/BigDL,qiuxin2012/BigDL