Updated jol to 0.2 to resolve the slow startup problem due to heavy GC
Add queries that fail before starting to expiration queue

This was a bug introduced in https://github.com/facebook/presto/pull/1917
Fix handling of null collections in unnest
Handle non-scalars in json_array_get
Precompute hashes for nodes that need hashes

1. Add abstraction for hash generation
2. Add an optimizer that uses optimized hash generation for all nodes
that use groupByHash and lookup source
3. Modify operator test to run for both with and without hash generation enabled
4. Add a config option and session property to turn the feature on/off
Make JsonType comparable
Expose at_timezone hidden function
Improve error messages for Hive partition value parsing
Fix resource leak in query queue

Queries can transition to the CANCELED state before they are started. In
particular, this happens if a user cancels their query while it is
queued. In this case, the state change listener is never called, because
the query is already finished, and this leaks one slot in the query
queue.
Add release notes for 0.83
Add release notes for 0.83
[maven-release-plugin] prepare release 0.83
[maven-release-plugin] prepare for next development iteration
Disallow window functions order or partition on noncomparable types
Fix COUNT(*) in information_schema and sys tables
Improve error message when using DISTINCT with non-comparable type
Fix json parsing for non numeric numbers (nan and inf)
Don't override remotely-accessible flag when locationAwareScheduling=false
Fix explain help text
Add Xerial Snappy to Hive for Parquet