JsonPath with bracket-notation

Add explicit tokenization step to JSON path
Add HyperLogLog support to cast to varbinary
HyperLogLogType and VarbinaryType return SqlVarbinary object
Add Varbinary hex, base64, base64url functions
Add documentation for binary functions
Rewrite count(constant) to count(*)
Narrow return type of LocalQueryRunner.printPlan()
Remove extra newline
Improve aggregation framework

* Introduce a compiler for accumulators
* Introduce compiler for aggregation functions
* Add annotations, so that aggregation functions can be defined as a combination of static methods
* Benchmarks show ~10% performance improvement on TPCH query 1, and ~30% speed up for SUM()
Remove AbstractSimpleAggregationFunction
Add unit test for evaluate_classifier_predictions
Add support for aggregation functions with multiple arguments
Add support for overloaded aggregations in compiler
Remove broken approx_distinct(boolean) function
Refactor approx_distinct to use new aggregation framework
Refactor COUNT_IF
Refactor approx_set
Refactor count aggregation
Rename AggregationFunctionMetadata
Add support for approximate aggregations in compiler