TPC-H: Stream id for Q15

[perdelt]

Use this (accepted Variant A) for PostgreSQL:

with revenue (supplier_no, total_revenue) as (
select
l_suppkey,
sum(l_extendedprice * (1-l_discount))
from
lineitem
where
l_shipdate >= date('1996-01-01')
and l_shipdate < date('1996-01-01') + interval '3' month
group by
l_suppkey)
select
s_suppkey,
s_name,
s_address,
s_phone,
total_revenue
from
supplier,
revenue
where
s_suppkey = supplier_no
and total_revenue = (
select
max(total_revenue)
from
revenue
)
order by
s_suppkey;

[perdelt]

parameter.defaultParameters['STREAM'] can now be set at constructor of benchmarker class. This also helps in reordering of queries depending on the stream. Q15 is using CTE now, so issue is closed anyway.