[TRAFODION-2917] Refactor Trafodion implementation of hdfs scan for text formatted hive tablesPart-1 changes.Created a new class org.trafodion.sql.HDFSClient. Any direct HDFS accesswill be routed to this class via JNI instead of using libhdfs.Modified the existing code expect for the following to route the HDFS request via this class1. LOB access2. Direct HDFS scan of the table3. Sample data creation during update statsAdded a new class org.trafodio.sql.HdfsScan for scanning one or many ranges of a Hivetext formatted table. This class will be used for Direct HDFS scan in near future.