[Wood Stud Wall] Add Support for Southern Pine

[buddyd16]

add in support for Southern Pine Lumber

[buddyd16]

I have a method in mind that will revamp the class a bit. Essentially mimic the AISC shape database and create a dictionary for each species with sub dictionaries for each grade, the grade would then include the reference design values and any factors specific to that lumber type, mostly looks like Cf is what gets impacted between lumber types at least in the 2-4x stud dimensions.
ie. {Alaska Cedar: {Select Structural:fb,ft,fv,fcperp,fcpara,E,Emin,Cf}....{Utility:fb,ft,fv,fcperp,fcpara,E,Emin,Cf}}