More detailed documentation for buildings floorspace

[sspeizer]

Hi all, more detailed documentation about setting building floorspace satiation values and the building_SSPx.xml add-on files and how to use them would be helpful. Something similar to what was in the old documentation (https://jgcri.github.io/gcam-doc/v3.2/Buildings) would be a great starting point.

[sspeizer]

I found more details in the per capita floorspace section here https://jgcri.github.io/gcam-doc/demand_energy.html which is helpful, but more information about the add-on files (in that section or otherwise) would be great too