Redirect std::cout and std::cerr

[dmed256]

Jupyter doesn't redirect IO messages coming directly from the C++ API. We need to somehow wrap std::cout and std::err usage in occa to allow for redirects.

We would take wanted outputs and wrap them in some C API methods

• std::cout would use PySys_WriteStdout

• occa::warn and occa::error could use PyErr_WarnEx for that Jupyter pretty print