Benchmark Result Row Count

[stanbrub]

The benchmark framework reports on the number of rows used to scale the measured operation. However, depending on the operation the result table size may be a factor in assessing performance. For example, an operation reducing 100 million rows to 10 rows may be assessed differently than an operation reducing 1 million rows to 10 rows. There is also the benefit of another number to track to ensure each benchmark test is comparable to the previous run.

• Added a result_row_count column to benchmark results
• Make it optional: Should -1 be used for benchmarks where result count does not apply?
• Update appropriate tables in the benchmark-tables.py script in GCloud