change loop length over PdepNetworks in search for maximum leak rates
change loop length over PdepNetworks in search for maximum leak rates

- numPdepNetworks = self.networkCount was the number of PdepNetworks
ever created in that model

- len(self.networkList) is the number of actually existing PdepNetworks
at any time

fixes #176

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