At one million indexes per second, half a million years to run out of indices

Replace missing headers as needed

See #16

Python part still needs to be fixed, almost there, compiles in clang again

The key point is to speed up compilation, and make it easier to develop, by using the packaged C++ interface more extensively

No warnings from teqp code, all from externals

Closes #41

Try to push this hotfix today

Helpful for debugging

Tiny updates, nothing too serious

Closes https://github.com/usnistgov/teqp/issues/30