Use buildingenvelopedata.org in WINDOW and THERM

[christoph-maurer]

First, IGSDB is implemented in with a version for testing in September 2023 and wider public testing in September 2024. In this first step, IGSDB is part of buildingenvelopedata.org.

Second, the connection to buildingenvelopedata.org will be implemented in WINDOW and THERM. This would be great for example for urgent building projects which need newly measured data soon in WINDOW and THERM.

[christoph-maurer]

Maybe a version this year. Maybe in parallel? Would be good for pyWinCalc.