Load only thermo libraries

To reduce the database pickle size, thermoEstimator now only loads thermo libraries.
Allows RMG to continue when there is a duplicate species

Originally, RMG stops if any two species are identical in the initial species list. Since this can happen frequently when using thermoEstimator with a large list of spcies, I changed it, so that RMG
ignores the duplicate, and continue execution.
Added memory usage information in thermoEstimator

Optional positional argument is added to change chunk size.
Changed the scope of shared variable qmValue.

I am still not sure the best way to do it.
Fixed the problem in naming the Thermo Library