TPC-H queries with subslect with aggregate are not working (queries 2, 11 and 18)

This is blocker for MCOL-6238 and a followup to MCOL-6251.

The gist of the problem is specified in 6238, two queries were fixed in 6238 and 6251 and three of them are still do no work. This is so because they contain aggregates and, possibly, implicit group by.

As mentioned in 6251, most probably, the problem is in incorrect enumeration of SimpleColumn's in subquery-with-aggregate. One should look into getSimpleColsExtended() function in simplecolumn.cpp.