Cython code to more quickly evaluate ShermanMorrison combinations as need by kernel ecorr in Enterprise.

The FastShermanMorrison add-on to Enterprise can be easily installed straight from github using

pip install git https://github.com/nanograv/fastshermanmorrison.git

From Pypi, you can do

pip install fastshermanmorrison-pulsar

Conda support is in testing stage. Apple silicon arm processors are not supported yet, but on other architectures you can do

conda install -c vhaasteren fastshermanmorrison-pulsar

Availability on conda-forge is upcoming in a later release