Basic operation of OpenCV Pose Estimate achieved: needs refinement.
Cleanup.  No significant code functionality change.
Cleanup.
Pilot cube moved to side, transparent overlay cube now active, but has a
rotational calibraiton problem.
Eliminate overlay cube: no longer in use.
Class rename: no functional code change.
A collection of small cleanup, clarification, code beautification and
bug fixes.
Now defined camera to be a center of world coordinates, and cube to be
about 10 units (as calculated by pose esitmator) down Z axis.  This adds
clarity to OpenGL code.
Achieve reasonable operation of opencv pose esitmator, however manual
corrections params provided for.  Only active on overlay cube.
Cleanup and fleshing out.
Re-enabled GL arrows.