This needed the following additional changes:

- Python needs full OpenSSL support for distutil/setuptools
- Enable ensurepip so that sipbuild can install its dependencies
- Python.framework ignores PYTHONPATH, so add our site-packages to sitecustomize
- Synchronize all OSX deployment target versions
- Ensure make install runs with j1 (install race conditions)
- Point the site-packages symlink to the Framework directory
- osxdeploy: Fix the site-packages paths and also trim pip, PyQt_builder, and sipbuild.