Add zone load and HVAC system auto-sizing to Spawn

[mwetter]

This issue is to update the Spawn coupling to allow obtaining sizing information for zone HVAC and system HVAC, as described in https://lbl-srg.github.io/soep/softwareArchitecture.html

The implementation on the EnergyPlus side will be done after upgrading to the latest version of EnergyPlus. To progress on the Modelica implementation, it will initially be done in the source code in the package EnergyPlus_9_6_0 and then moved to EnergyPlus_xxx after the Spawn binaries and models are updated.