CLDCONNECT-1850 :  Update HDFS Java Client to support Hadoop 2.4.x hosts

1. Updated the HDFS Java Client
2. Fixed all the existing operations to support Hadoop 2.4.x hosts.
3. Fixed the functional test cases.
4. Updated the CHANGELOG.md
I think since we are upgrading this connector for Hadoop 2.4.0 which is anyway a major change from earlier supported version of 1.0.4, I think we should change the major version to 4.0.0 for the connector.