Means to set some sane defaults for storm worker hosts

[ianoc]

It would be good to add a utility to set some good WORKER_CHILDOPTS for storm:
I've had good success with using something like:
val heapSize = 20000
val permSize = 128
val newGenRatio = 0.8f
val compressedOops = if(heapSize > 30000) "" else " -XX:+UseCompressedOops"
val newGen = (newGenRatio * (heapSize - permSize)).toInt
val vmSettings = "-Xmx%dm -Xms%dm -Xss256k -XX:MaxPermSize=%dm -XX:PermSize=%dm -XX:NewSize=%dm -XX:MaxNewSize=%dm -XX:MaxTenuringThreshold=2 -XX:SurvivorRatio=6 -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:+CMSParallelRemarkEnabled -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -XX:+AggressiveOpts %s -XX:+UseCompressedStrings".format(heapSize, heapSize, permSize, permSize, newGen, newGen, compressedOops)

An extension of this would be around setting number of workers too.

WorkersPerHost = X
NumHosts = Y
RamPerHost = Z

and use that to set these parameters and the number of workers also.