remove deprecated use of spawn
remove deprecated use of spawn

mattyb149/blinkdb,alabid/blinkdb,lzshlzsh/shark,mattyb149/blinkdb,lzshlzsh/shark,alabid/blinkdb,sameeragarwal/blinkdb,sjyk/sampleclean,mapr/shark,sameeragarwal/blinkdb,amplab/shark,mapr/shark,sjyk/sampleclean,sameeragarwal/blinkdb,sjyk/sampleclean,amplab/shark,lzshlzsh/shark,amplab/shark,mapr/shark,mattyb149/blinkdb,alabid/blinkdb