Suite sparse installation

Hi,

Here is a solution to solving the suite-sparse installation problem.

When suitesparse is installed in the different location than the default one, and scikit-sparse cannot find it to load cholmod. Then try this: SUITESPARSE_INCLUDE_DIR=/usr/local/include SUITESPARSE_LIBRARY_DIR=/usr/local/lib /usr/local/bin/python3 -m pip install scikit-sparse