Ported Fault Tolerant AbstractHDFSExactlyOnceWriter operator from guava poc

     * Added counters to track total time and bytes written.
     * refactored HdfsExactlyOnceOutputOperator to use AbstractHDFSExactlyOnceWriter
     * deprecated AbstractHdfsFileOutputOperator
     * removed obsolete AbstractHdfsOutputOperator
     * removed obsolete AbstractHdfsRollingFileOutputOperator
     * removed obsolete HdfsOutputTupleInterface
     * removed unused benchmark HDFSBothInputOutputOperatorsBenchmark
     * modified HDFSOutputOperatorBenchmark to use fault tolerant writer
     * Updated Fraud detection demo to use fault tolerant writer
     * Updated map reduce demo to use fault tolerant writer
Isn't this equivalent of clearing offsets?