An alternate attempt at #992

May as well update the build command's build_lib as well
Merge pull request #992 from astrofrog/fix-pure-python-build-dir

Make pure-python affiliated packages separate Python 2 and Python 3 builds
Fixed typo in docs/table/index.rst
Merge pull request #1047 from amiruna/placeholder

Fixed typo in docs/table/index.rst