Convert duplicate reactions to MultKinetics rate expressions when importing old libraries.
Convert duplicate reactions to MultKinetics rate expressions when importing old libraries.

When reading old (RMG-Java) style reaction libraries, things which were marked
DUPLICATE are converted into single reactions with MultiKinetics. Note that
the entries are not renumbered, so there will be some missing indices.

pierrelb/RMG-Py,pierrelb/RMG-Py,comocheng/RMG-Py,chatelak/RMG-Py,nyee/RMG-Py,faribas/RMG-Py,KEHANG/RMG-Py,nickvandewiele/RMG-Py,nickvandewiele/RMG-Py,chatelak/RMG-Py,enochd/RMG-Py,nyee/RMG-Py,KEHANG/RMG-Py,enochd/RMG-Py,comocheng/RMG-Py,faribas/RMG-Py