Update etl scripts

Contains environments variables for etl scripts. Factorize some code and creates
symbolic links for hraven-core.jar and hraven-etl.jar if needed. Etl scripts now source this file.

Source hraven-etl-env.sh and add default values for costFile and rawFileSizeLimit.
Also calls jobFilePreProcessor.sh and jobFileProcessor.sh  with right arity and parameters from now.

source hraven-etl-env.sh

source hraven-etl-env.sh and add defaultRawFileSizeLimit to parameters

exports HBASE_CLASSPATH
Now set a default value for hadoop property mapreduce.map.memory.mb
which is not set in yarn conf by default