Different calculations values between mac and windows

[vidanovic]

When running TestDoubleClearIndoorShadeAir in Windows vs Mac, they produce slightly different results. Problem seems to be that one multiplication operation is giving different results between windows and mac. I have tried same thing in python and did obtain the same results:

`
STEFANBOLTZMANN = 5.6697e-08
Emissivity = 0.83999999999999997
Temperature = 276.29432700032805

result = STEFANBOLTZMANN * Emissivity * Temperature**3

print(result)
`

This produces 1.0045123242711191 on windows and 1.0045123242711194 on mac.
I suspect that this is what causing differences at the final results since iterations are performing differently from this point onwards.