For the role descriptor

Cross-correlation now working

See merge request tpurcell/cpp_sisso!8

can set a maximum cross correlation for selected features

When a feature was constant across one task but not all it lead to an issue
This is now fixed by ignoring all scores with a score not between 0.0 and 1.0

About a 2x speed up for l0-normalization

Scores + HR expressions in SIS_summary.txt
CR expressions in selected_features.txt

remove some branches and redundent calls

Occiasionally selects the wrong first feature for 0.2

hopefully make it easier to install

Clarify some things to make less confusing

Remove conflict with pySISSO

don't need to have readelf and ls lines

This should resolve linking issues

See if that solves linker errror

cahnge PYTHON_LAPACK_LIBS

See if that fixes problems with pytest

See if pytests will actually work

should fix some of the problems with pytest

might fail due to mpi4py