Revert "See the performance impact of not using hwloc"

This reverts commit b18fa4801d8333d4a1a6e90839ebb26a96d435e1.

Brad mercilessly demanded I test tcmallc+qthreads for at least one more day.
Merge pull request #242 from ronawho/qthreads-as-default

Revert "See the performance impact of not using hwloc"

This reverts commit b18fa4801d8333d4a1a6e90839ebb26a96d435e1.

Brad mercilessly demanded I test tcmallc+qthreads for at least one more day.