First attempt at determinism in the reactant-centered model:
- added a series of autoarcs on location updating
- added a "c'==0" invariant on location not_reacting
- transitions going from not_reacting to updating do not reset c anymore
Now trying to add a yet better way to get determinism, but centered on 0
uncertainty only: if a reactant on which I depend reacts before me (c <
tL), I wait for any other reactant (if there are others reacting at this
same instant) on which I depend before doing update() and deciding
whether to reduce the current value of c. This allows for more
consistent behavior.