972110 swimming pool

Changes and additions needed to model indoor swimming pools; this work is ready for review
@RKStrand Correct, there are several \reference HeatTranBaseSurfNames to establish which objects are part of this group, but I did not see any \object-list HeatTranBaseSurfNames.  If you want to make it exclusive to floors, the perhaps you want to make a new reference name just for objects which could be a floor (that's just two or three classes, I think).