updating structure to use d3 style update add delete
working on rendering pathway using correct d3 methods
successfully getting display working using d3 methods
both scalable and nonscalable shapes are working at the proof of concept level
now getting shapeType instead of hard-coding in just 'roundedRectangle'
updated to handle uniform and nonuniform scaling for shapes
reworked data model, got more of the pathway elements being displayed and re-enabled details frame
merge