Resolve "parse reaction stochiometry"
Due to that there is a change with REST API and plugin API responses:
Stoichiometry is associated with reaction node (but not with the alias/species). Therefore when checking for reaction products/modifiers/reactants the result will provide you with the Product/Modifier/Reactant structures instead of aliases. Those structures contain getAlias method that will return you the previously stored Alias structure.
Closes #368 (closed)