See the performance impact of not using hwloc

[This is in my playground scripts, not the real perf testing]

I'm curious. If there's no performance benefit to using hwloc, it seems like
it'd be nice to turn it off by default since it increases startup times, and it
would remove a 3rd party dependency for our defaults.
Merge pull request #240 from ronawho/qthreads-as-default

See the performance impact of not using hwloc

[This is in my playground scripts, not the real perf testing]

I'm curious. If there's no performance benefit to using hwloc, it seems like
it'd be nice to turn it off by default since it increases startup times, and it
would remove a 3rd party dependency for our defaults.