Port the obs_monocam package to pybind11
Note that obs_monocam is part of lsst_distrib
Wrap lsst_distrib with pybind11
obs_monocam has no unit tests. However, I examined the code and found nothing that required changing for pybind11 compatibility.
I did not bother to create a tickets/DM-8467 branch because no changes were required.