Expand testing

[dswigh]

1. find a case for test_rxn_input_extractor and handle_rxn_obj that contains ice
2. Check that solvents csv is well formed
3. Test all 4 options for handling unresolvable names (TFF, FTF, FFT, FFF): set_unresolved_names_to_none_if_mapped_rxn_str_exists_else_del_rxn, remove_rxn_with_unresolved_names, set_unresolved_names_to_none
4. is_mapped function in cleaning
5. Check that there are no solvents outside solvents label, unless it has a mapped atom (and is thus a reactant).