12.86. Release 0.160

General Changes

Fix planning failure when query has multiple unions with identical underlying columns.
Fix planning failure when multiple IN predicates contain an identical subquery.
Fix resource waste where coordinator floods rebooted workers if worker comes back before coordinator times out the query.
Add Lambda Expressions.

Fix planning failure when inserting into columns of struct types with uppercase field names.
Fix resource leak when using Kerberos authentication with impersonation.
Fix creating external tables so that they are properly recognized by the Hive metastore. The Hive table property EXTERNAL is now set to TRUE in addition to the setting the table type. Any previously created tables need to be modified to have this property.
Add bucket_execution_enabled session property.