WaterSteam properties implementation using Analytical Jacobian

As seen during !13 (merged), the notation ThermoSysPro_AJ was present in some files (ThermoSysPro/Properties/WaterSteam/IF97_packages.mo, ThermoSysPro/Properties/WaterSteamSimple/SimpleWater/Pressure_sat_hl_der.mo and ThermoSysPro/Properties/WaterSteamSimple/SimpleWater/Pressure_sat_hl.mo).

According to @audrey.jardin, "AJ" stands for Analytical Jacobian. A version of ThermoSyrPro with analytical Jacobian (for watersteam properties) was developed in the past. We may conclude here that the AJ version was merged in the default one, but this should be checked.