V6 Display: GPU Tessellation on by default

Ok, this feature was actually on by default in last week’s WIP, but there were a few nasty bugs that kept me from wanting to “show off”.

The latest V6 WIP has GPU tessellation on by default. This feature is now responsible for drawing all polysurface wires, extrusion wires, and curves when enabled. Hopefully you won’t notice any difference visually but will see an improvement in performance when dealing with heavier models.