GlassLayer has too high/too low temperatures if conductivity is near zero.

[mwetter]

The glass surface temperatures are outside the boundary condition temperature, e.g., too high on the 20 degC room side, too cold on the 0 degC outside for conductivity near zero. The equations in Buildings.HeatTransfer.Windows.BaseClasses.GlassLayer seem to be fine.
Maybe the issue is at Buildings.HeatTransfer.Radiosity.OpaqueSurface?

To reproduce, run

simulateModel("Buildings.HeatTransfer.Windows.BaseClasses.Examples.GlassLayer(nonSha(k=0.001))", method="dassl", tolerance=1e-06, resultFile="GlassLayer");

[mwetter]

This is now merged to the master branch.