Squashed commit of the following:

commit a760df6f84a7af3e6f16db3368cfebf6babb72cc
Author: RashmiDR <rashmi@datatorrent.com>
Date:   Mon Feb 24 14:58:27 2014 -0800

    demos for benchmarking HDFS operators, fixes #MLHR-825
Merge pull request #731 from RashmiDR/hdfsPerformanceApps_pull

Squashed commit of the following: