Add to machine util, start to integrate test_bench
- debugging issue where GOMP_CPU_AFFINITY and taskset are
properly specified with a range e.g. 4-47 on the command line
for pytest, but the machine util sees process affinity as just
4; this does not happen when using the same command line with
python instead of pytest and invoking the machine util
- need to verify the extra json file size incurred by logging
machine state every benchmark
