Enhance the Netezza Connector for Sqoop

SQOOP-846 introduced the Netezza connector which was later enhanced with hcatalog integration (SQOOP-931) even for direct mode SQOOP-1167.

Based on community feedback, it seems a few options to the direct mode export of the Netezza connector is desired.among others allowing control chars, truncate the string, etc. Even though allowing arbitrary options was initially introduced, it was removed from the connector before the initial version. The idea is to specifically enumerate explicit list of options.

Also, there is a need to consolidate the log files of the export process so that users can parse the logs post the export job.