HIVE-24908: Adding Respect/Ignore nulls as a UDAF parameter is ambiguous

[kasakrisz]

What changes were proposed in this pull request?

1. Add respectNulls boolean property to GenericUDAFParameterInfo.
2. Map this property to Windowing specification/definitions objects.
3. Introduce property to WindowFunctionDescription which show whether the function supports handling null treatment settings.

• If the supportNullTreatment property is not set explicitly the UDAF does not support null treatment and the compiler throws SemanticException if specified.
• If the supportNullTreatment property is set to true but the function call does not specify null treatment the default null treatment is used: RESPECT NULLS
• The specified null treatment is used othervise.

Why are the changes needed?

This patch is a follow-up of #2060. See jira for details.

Does this PR introduce any user-facing change?

Yes. When calling lead or lag functions by specifying RESPECT/IGNORE NULLS

• and no default value parameter is given RESPECT/IGNORE NULLS are not passed as default value parameter: NULL is returned if rows has no corresponding following/preceding rows
• and default value parameter is given RESPECT/IGNORE NULLS are not passed as default value parameter: no Exception is thrown

How was this patch tested?

mvn test -Dtest.output.overwrite -DskipSparkTests -Dtest=TestNegativeLlapLocalCliDriver -Dqfile=nulltreatment.q -pl itests/qtest -Pitests
mvn test -Dtest.output.overwrite -DskipSparkTests -Dtest=TestMiniLlapLocalCliDriver -Dqfile=windowing_navfn.q -pl itests/qtest -Pitests