SPARK-1734: spark-submit throws an exception: Exception in thread "main"...

... java.lang.ClassNotFoundException: org.apache.spark.broadcast.TorrentBroadcastFactory

Author: witgo <witgo@qq.com>

Closes #665 from witgo/SPARK-1734 and squashes the following commits:

cacf238 [witgo] SPARK-1734: spark-submit throws an exception: Exception in thread "main" java.lang.ClassNotFoundException: org.apache.spark.broadcast.TorrentBroadcastFactory