Ryan add xai

[rhsimplex]

Not for merging, only to compare differences. New arguments: -c for "no intermediate FCN" and -g for "gini coefficient", which is a float (default 0).

I ran my tests with:

python -u compchemdl/models/mtnn_gc.py -t data/TEST_DATA_DIR/ -n gini_run_test -g 5 -o gini_temp_test -s Canonical_Smiles -y Value -i Compound_No -f Fold -c -q 10.0 -v 256 256 256 -e 10

where TEST_DATA_DIR contains a small amount of data (1000 per target).