Change CANNOT_DROP_TABLE to PERMISSION_DENIED
Add NOT_SUPPORTED error code
Skip warning when drop table cleanup fails

We try to cleanup any created tables in tests by dropping them, but the
drop fails if they don't exist, which usually means the table was never
created in the first place. Warning about this is confusing because the
warning is printed before the test failure and obscures the actual cause
of the test failure.
Add table rename support

Syntax: ALTER TABLE old RENAME TO new

This feature is disabled by default for the Hive connector.
Enable by setting 'hive.allow-rename-table' to 'true'.
Add documentation for ALTER TABLE
Added client timeout for long running queries in PerfTest