Calculation of heats of vaporization & other properties

[leeping]

Currently, FB includes kinetic energy terms in the gas and liquid phases when computing the heat of vaporization. I am pretty sure these terms are supposed to analytically cancel out in classical mechanics, so these terms should also be removed from the calculations.

This issue may also extend to the calculation of thermal expansion coefficients and heat capacities, where the kinetic energy term shows up in the expressions but we may have analytic expressions for them. We should think about whether the proposed fix for ∆Hvap should also extend to these other properties.