Issue8 annex2 aix

Created by: marcusfuchs

This is a major change. This merges the Annex 60 library to be an integral part of AixLib. A script in Resources.Scripts performs this merge automatically, given that the MODELICAPATH is set correctly and buildingsPy is installed. All water-based models have been changed to use Annex 60 base classes, introducing the Modelica.Fluid concept to this part of the library. All these models have been put in the corresponding packages of AixLib.Fluid, the structure of which is imported from Annex60.Fluid. There are often similar models from the Annex 60 library in these packages. Thus, this version can serve as a foundation for cross-comparisons and model consolidation. We should see about whether to use Annex60 components or keep the simple AixLib implementation for each case (e.g. pipes, pumps, etc.)

The air-based models are still in the package AixLib.HVAC. To convert these to Annex60 base classes would require some work that may not be justified, as for most components there are already Annex60 implementations. Arguably better ones for many use cases. Therefore I suggest to convert the remaining models from AixLib.HVAC only as needed. If not needed, the package may be deleted after a transition period.

Could I please ask you guys to review the new structure and give your opinion before merging?