Implement WingGeom::ComputeCenter() to set rotation center along root chord.
Simplify default wing to single section.
Implement Loop Stack option.
Fix tabs to spaces in ResetUWSkip
Fixed Script to XML bugs and warnings

Conflicts:
	src/geom_core/WingGeom.cpp
Fix missing commas in DegenGeom CSV file as reported by Erik Olson
Make container (stl) helpers const-correct.
Passing strings by value is a premature pessimization given that C++11 strings *can't be* implicitly shared and thus are expensive to copy.