[SP-1082] Backport of [PDI-11269]

NPE when date format locale is null causing carte cluster trans to fail

cherry-pick: https://github.com/pentaho-skarmali/pentaho-kettle/commit/ecce0a6af69b5d54050a0413aaedc11c3e5ff6a0
issue: http://jira.pentaho.com/browse/SP-1082