Fix inconsistencies in aggregations and query library functions.

[deephaven-internal]

This issue was auto-generated

PR: deephaven/deephaven-core#5368
Author: chipkent

Original PR Body

Aggregation operations in query library functions and built-in query aggregations are inconsistent. This PR makes them consistent. Query library functions were changed.

• percentile now returns the primitive type.
• sum returns a widened type of double for floating point inputs or long for integer inputs.
• product returns a widened type of double for floating point inputs or long for integer inputs.
• cumsum returns a widened type of double[] for floating point inputs or long[] for integer inputs.
• cumprod returns a widened type of double[] for floating point inputs or long[] for integer inputs.
• wsum returns a widened type of long for all integer inputs and double for inputs containing floating points.

Note: Because the types have changed, the NULL return values have changed as well.

Resolves #4023

[margaretkennedy]

#207