Feature: Should have an option to calc thermo of all species accesible in a flux diagram at a certain tolerance

[alongd]

In addition to species selection by SA, we should also select by flux. E.g., generate a flux diagram at a requested tolerance and add all the included species to the calc list.

[alongd]

Another note to ourselves re species selection: should calculate thermo for all species participating in very exothermic/endothermic reactions in the core (very exothermic reactions could be a false flux sink)

[xiaoruiDong]

I had a script to do so, to extract species in a flux diagram