Fix bugs in Mass Action recognition code for Mass Action kinetics where the metabolites have a stoichiometry different from 1.
Fix bugs in Mass Action recognition code for Mass Action kinetics where
the metabolites have a stoichiometry different from 1.

jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI