v4.0.0

Changes from v3.0.0:

• (Breaking Change) Add op.array_agg aggregation function, remove prior op.values definition .
• (Breaking Change) Add op.array_agg_distinct aggregation function, remove prior op.unique definition.
• Add op.object_agg aggregate function.
• Add op.greatest and op.least functions, corresponding to Math.max and Math.min.
• Add op.compact function to filter invalid values from an array.
• Add support for Map and Set instances to op.has(), op.keys(), and op.values().
• Add op.entries() function, with support for Object, Map, and Set instances.
• Add table columnArray() method.
• Update parser to rewrite Math.max and Math.min to use greatest and least.
• Fix dedupe() to produce ungrouped tables.