Fix crash when enabling Controller Debug display.
plStringify ControllerDebugDisplay.

plStringification of plPXPhysicalControllerCore::IDrawDebugDisplay
and general clean-up.  Also changed to only display
avatar collisions heading if any exist to show.
Build plPageOptimizer.
Merge pull request #271 from Deledrius/DebugControllerDisplay_Crashfix

Fix crash when enabling Controller Debug display
Use puts instead of printf.
Merge pull request #272 from dpogue/optimizer

Build plPageOptimizer.
Re-define nil as nullptr, cleaning up some potential issues along the way