Add massif tool to profile memory in benchmarks

Based on discussions with @federico, adding the massif tool to benchmarking script. I couldn't find a way to run two valgrind tools at once so all benchmarks are run twice. Once with cachegrind and second time with massif. The massif output file is processed to read the snapshot data and find the peak memory consumption snapshot. The total peak memory consumption is submitted as the metric value for memory benchmarks.