Separated methods pertaining to StructuralMaterial outside of the ConvertAnalyticalStick.cs file. Didn't make sense that these functions were in the ConvertAnalyticalStick.cs when the ConvertAnalyticalSurface.cs referenced them

Material properties were sent as revit internal units. Inconsistent with the Revit model / project units. These can't be used for connection applications (e.g. receiving analytical elements in ETABS)

ETABS currently only created properties for Element2Ds with a CSIProperty2D, but what about Property2D? These should also be received without us defaulting to the "Slab1" ETABS section.

Walls were previously assigned with slab sections which is incorrect. The WallPropertyToNative() was implemented (previously raised a ConversionNotSupportedException for some reason)

Testing on Revit 2022 - ETABS connection