Added void forest::load(const char* const path) to random_forest_test and void forest::save(const char* const path) const to random_forest_train
Added load() to receptor and ligand
Added feature.hpp
Added static const scoring_function sf; to inline feature()
Revised scoring_function::score to accept r2 instead of r in order to avoid including <cmath> in feature.hpp
Revised load() and save() to accept const string instead of const char* const
Changed sqrt(ds) to ds
Added rf-prepare
Revised a comment
Added csv header
Added \n to the end of csv header
Added rf-prepare to README.md