* NN optimization for hdfs data segments.
* HdfsDataSegmentKiller, HdfsDataSegment finder changes to use new storage
format.Docs update.
* Common utility function in DataSegmentPusherUtil.
* new static method `makeSegmentOutputPathUptoVersionForHdfs` in JobHelper
* reuse getHdfsStorageDirUptoVersion in
DataSegmentPusherUtil.getHdfsStorageDir()
* Addressed comments.
* Review comments.
* HdfsDataSegmentKiller requested changes.
* extra newline
* Add maprfs.