[maven-release-plugin] prepare release 0.66
[maven-release-plugin] prepare for next development iteration
Fix generating invalid query plans
Fix resource leak in HiveSplitSource when queries terminate early

Hive queries that don't consume all splits can leak threads that get
stuck trying to acquire the semaphore that controls how many HDFS
tree walkers run concurrently.

This change makes split sources closeable to allow for proper cleanup.
Set thread names for hive split producer and hdfs walkers
Categorize invalid VARCHAR casts
Switch to Airlift Threads class
Fix thread naming for single threaded executors
Fix warnings in HiveClient
Replace instanceof with checkType in Hive connector
Refactor formatting for SortItem
Add formatting for every statement type
Move parser utility classes out of tree package