Hive JDBC should do timestamp conversions in UTC

Hive moved away from java.sql.Timestamp to java.time.LocalDateTime ( https://issues.apache.org/jira/browse/HIVE-12192 ), in order to be consistent w.r.t timestamp field irrespective of the current time zone. For example: for time zones like America/Los_Angeles that alternate between PST and PDT, time can be shown based on effective current time zone, which is set in the current SQL session. Hive JDBC handler should follow suit and use LocalDateTime ( A date-time without a time-zone ), when doing the conversion, so that original timestamp returned by Hive is preserved. 

This issue is also more pronounced because of this bug in Java -> 

https://bugs.java.com/bugdatabase/view_bug.do?bug_id=JDK-8258586 .