Fix literal handling in Window functions

[xiangfu0]

Fix literal handling in Window functions:

• WindowNode has a field constants to keep all the literals
• The InputRef index could map to first windowInput then constants
  • e.g. assume the windowInput size is 2 and constants size is 3, then we may found InputRef from $0 to $4, and $2 to $4 are the constants references.
• Update the arguments list RexInputRef pointing to the corresponding RexLiteral.

Sample query:

SELECT DaysSinceEpoch,
  Distance,
  LAG(Distance, 5, 10) OVER (
    ORDER BY DaysSinceEpoch
  ) AS previous_day_sales,
  Distance - LAG(Distance, 5, 10) OVER (
    ORDER BY DaysSinceEpoch
  ) AS difference
FROM airlineStats;

WITH tmp AS (
  select count(*) as num_trips,
    DaysSinceEpoch
  from airlineStats
  GROUP BY DaysSinceEpoch
)

SELECT DaysSinceEpoch,
  num_trips,
  LAG(num_trips, 2) OVER (
    ORDER BY DaysSinceEpoch
  ) AS previous_num_trips,
  num_trips - LAG(num_trips, 2) OVER (
    ORDER BY DaysSinceEpoch
  ) AS difference
FROM tmp;