- this fixes a mistake from commit 821dc915
- it also consistently use the thermal expansion coefficient
- add code comments
now the material task dialog works with all fluid materials without errors or warnings
- since a while ThermalExpansionCoefficient is used, VolumetricThermalExpansionCoefficient is only used for the material task panel
- as already stated in a code comment, the unit of VolumetricThermalExpansionCoefficient is ThermalExpansionCoefficient, therefore we must check for ThermalExpansionCoefficient
- we must also check if ThermalExpansionCoefficient exists
- Adapt the existing fluid material cards to use the ThermalExpansionCoefficient
- also adjust values slightly according to various sources
Since a factor 1000 is a big mistake and air is the most common gas, please commit this also for FC 0.19
